This Oatmeal Blueberry Crumb Cake brings together juicy blueberries, hearty oats, and a buttery cinnamon crumb topping for a cozy homemade treat. The cake is soft and tender, with bursts of blueberry in every slice and a golden streusel layer that adds just the right amount of crunch.
It’s delicious served with coffee in the morning, enjoyed as an afternoon snack, or brought out for a casual brunch. The oatmeal gives the cake a comforting texture, while the blueberries add natural sweetness and a fresh, fruity flavor.
If you love blueberry coffee cake, oatmeal desserts, or simple homemade baking recipes, this crumb cake is a lovely one to keep on hand.
What Is Oatmeal Blueberry Crumb Cake?
Oatmeal Blueberry Crumb Cake is a tender cake made with oats and blueberries, finished with a buttery crumb topping.
The oats add a hearty texture, while the blueberries become soft and juicy as the cake bakes. A cinnamon-scented crumble on top creates a sweet, slightly crisp contrast to the moist cake underneath.
It’s a simple, home-style dessert that works for breakfast, brunch, or an everyday sweet treat.
Why You’ll Love This Recipe
- Juicy blueberries: Fresh or frozen blueberries bring fruity flavor to every bite.
- Hearty oatmeal texture: Oats add a little chew and make the cake feel comforting.
- Buttery crumb topping: A cinnamon streusel layer gives the cake a delicious finish.
- Easy to prepare: The batter comes together with common baking ingredients.
- Versatile: Serve it for breakfast, brunch, dessert, or an afternoon snack.
- Great for sharing: Bake it in one pan and slice it into squares.
Ingredients You’ll Need
For the cake
| Ingredient | Amount |
|---|---|
| Old-fashioned rolled oats | 1 cup |
| Milk | 1 cup |
| All-purpose flour | 1 1/2 cups |
| Baking powder | 1 1/2 teaspoons |
| Baking soda | 1/2 teaspoon |
| Salt | 1/4 teaspoon |
| Ground cinnamon | 1/2 teaspoon |
| Unsalted butter, softened | 1/2 cup (113 g) |
| Granulated sugar | 3/4 cup (150 g) |
| Large egg | 1 |
| Vanilla extract | 1 teaspoon |
| Blueberries | 1 1/2 cups |
For the crumb topping
| Ingredient | Amount |
|---|---|
| All-purpose flour | 1/2 cup |
| Old-fashioned rolled oats | 1/2 cup |
| Brown sugar | 1/2 cup (100 g) |
| Ground cinnamon | 1/2 teaspoon |
| Unsalted butter, melted | 1/4 cup (57 g) |
Ingredient Notes
Oats: Old-fashioned rolled oats provide a pleasant texture. Quick oats can work, but the cake may have a softer, less distinct oat texture.
Blueberries: Fresh blueberries work well. If using frozen berries, add them directly from the freezer without thawing, and fold them into the batter gently.
Butter: Softened butter helps create a tender cake. Melted butter is used for the crumb topping so it forms clumps.
Brown sugar: Brown sugar gives the topping a deeper flavor and helps it bake into a buttery crumble.
Kitchen Tools
- 8-inch square baking pan
- Mixing bowls
- Measuring cups and spoons
- Electric mixer or sturdy whisk
- Rubber spatula
- Fork or pastry cutter
- Parchment paper
- Wire cooling rack
How to Make Oatmeal Blueberry Crumb Cake
1. Soak the oats
Add the rolled oats and milk to a bowl.
Stir and let the mixture sit for about 15 minutes while you prepare the remaining ingredients. This softens the oats and helps them blend into the cake batter.
2. Prepare the pan and oven
Preheat the oven to 350°F (175°C).
Grease an 8-inch square baking pan or line it with parchment paper, leaving a little overhang to make the cake easier to lift out.
3. Mix the dry ingredients
In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon.
Set aside.
4. Cream the butter and sugar
In a large bowl, beat the softened butter and granulated sugar until light and creamy.
Add the egg and vanilla extract. Beat until combined, scraping down the sides of the bowl as needed.
5. Finish the cake batter
Add the soaked oats and milk mixture to the butter mixture.
Stir until combined.
Add the dry ingredients and mix just until no dry flour remains. Avoid overmixing, which can make the cake dense.
6. Fold in the blueberries
Add the blueberries and gently fold them into the batter.
If using frozen blueberries, fold them in while still frozen to help prevent excess color from streaking through the batter.
7. Make the crumb topping
In a separate bowl, combine the flour, rolled oats, brown sugar, and cinnamon.
Pour in the melted butter and mix with a fork until the mixture forms coarse crumbs.
If the mixture looks too sandy, press a few handfuls together to create larger crumble pieces.
8. Assemble the cake
Spread the cake batter evenly into the prepared pan.
Sprinkle the crumb topping over the surface, covering the batter as evenly as possible.
9. Bake
Bake for approximately 35–45 minutes, or until the top is golden and a toothpick inserted into the center comes out clean or with a few moist crumbs.
If the crumb topping browns too quickly, loosely cover the pan with foil for the final part of baking.
10. Cool and serve
Place the pan on a wire rack and let the cake cool for at least 20 minutes before slicing.
For neater squares, allow it to cool further before cutting.
Serve slightly warm or at room temperature.
How to Tell When the Cake Is Done
Check the center of the cake with a toothpick. It should come out clean or with a few moist crumbs, but not wet batter.
The crumb topping should be golden, and the center should look set rather than shiny or liquid.
Because blueberries release moisture as they bake, try the toothpick in a section of cake without a large berry.
Tips for the Best Blueberry Crumb Cake
Don’t skip soaking the oats
Allowing the oats to sit in milk softens them and helps create a more tender texture.
Measure flour carefully
Too much flour can make the cake dry. Spoon flour into the measuring cup and level it off, or use a kitchen scale.
Fold the blueberries gently
Stir just enough to distribute them through the batter. Overmixing can crush the berries and tint the cake.
Keep the topping crumbly
Mix the melted butter into the topping until it forms small clumps. Avoid mixing it into a smooth paste.
Let the cake cool before slicing
The cake is delicate while hot. Cooling helps it set and makes cleaner slices.
Fresh or Frozen Blueberries?
Both work well.
| Blueberries | How to use them |
|---|---|
| Fresh | Rinse, dry thoroughly, and fold gently into the batter |
| Frozen | Add directly from frozen; do not thaw first |
| Wild blueberries | Use the same amount; they may distribute more evenly because they are smaller |
Frozen berries may increase the baking time slightly, so check the center before removing the cake from the oven.
Variations
Lemon Blueberry Oatmeal Cake
Add 1 teaspoon of finely grated lemon zest to the batter for a fresh citrus flavor.
Blueberry Almond Crumb Cake
Add 1/4 teaspoon almond extract to the cake batter and sprinkle sliced almonds over the crumb topping.
Mixed Berry Oatmeal Cake
Replace some of the blueberries with raspberries or blackberries. Keep the total amount of fruit close to 1 1/2 cups.
Maple Oat Crumb Cake
Replace 2 tablespoons of the granulated sugar with maple syrup. The batter may be slightly softer, so check the baking time.
Extra-Cinnamon Crumb Cake
Increase the cinnamon in the topping to 1 teaspoon for a warmer spice flavor.
How to Serve Oatmeal Blueberry Crumb Cake
This cake is delicious on its own, but you can also serve it with:
- A cup of coffee or tea
- A glass of milk
- Plain or vanilla yogurt
- Fresh blueberries
- A light dusting of powdered sugar
- A spoonful of whipped cream
- A small scoop of vanilla ice cream
For brunch, cut the cake into squares and arrange them on a serving platter.
Storage
Allow the cake to cool completely before storing.
| Storage method | Approximate storage time |
|---|---|
| Room temperature, covered | Up to 2 days |
| Refrigerator, airtight container | Up to 5 days |
| Freezer, wrapped well | Up to 2 months |
The crumb topping may soften slightly during storage, but the cake will still be flavorful.
Can You Freeze Oatmeal Blueberry Crumb Cake?
Yes. Let the cake cool completely, then slice it into individual portions.
Wrap each piece tightly and place the portions in a freezer-safe container or bag.
Thaw in the refrigerator or at room temperature. For a freshly baked texture, warm a slice briefly in the oven before serving.
Frequently Asked Questions
Can I use quick oats instead of rolled oats?
Yes. Quick oats can be used, although the texture may be softer. Old-fashioned rolled oats provide a more noticeable oat texture in both the cake and topping.
Can I use frozen blueberries?
Yes. Add frozen blueberries directly to the batter without thawing. This helps reduce excess moisture and prevents the berries from breaking apart too much.
Why did my crumb topping melt into the cake?
The topping may have been too warm or too finely mixed. Make sure the butter is melted but not hot, and mix until coarse crumbs form.
Why is my blueberry cake soggy in the middle?
The cake may need more baking time, especially if the berries were frozen or especially juicy. Check the center with a toothpick and continue baking in short intervals if needed.
Can I make this cake ahead of time?
Yes. Bake it a day ahead, cool completely, and store it covered. You can serve it at room temperature or warm individual slices before serving.
Can I bake it in a different pan?
An 8-inch square pan gives a fairly thick cake. A larger pan will make a thinner cake and may reduce the baking time, so begin checking for doneness earlier.
Recipe at a Glance
| Detail | Information |
|---|---|
| Recipe | Oatmeal Blueberry Crumb Cake |
| Prep Time | 20 minutes |
| Cook Time | 35–45 minutes |
| Total Time | About 1 hour |
| Yield | 9 squares |
| Category | Breakfast, Dessert |
| Method | Baking |
| Cuisine | American |
| Main Flavor | Blueberry, cinnamon, oats |
Approximate Nutrition
Nutrition is estimated and will vary depending on the brands and exact ingredients used.
| Nutrient | Per serving |
|---|---|
| Calories | 365 kcal |
| Carbohydrates | 52 g |
| Protein | 5 g |
| Fat | 16 g |
| Saturated Fat | 9 g |
| Unsaturated Fat | 6 g |
| Trans Fat | 0 g |
| Cholesterol | 55 mg |
| Sodium | 250 mg |
| Fiber | 3 g |
| Sugar | 29 g |
Final Thoughts
This Oatmeal Blueberry Crumb Cake is a comforting homemade bake with a soft oat-filled crumb, juicy blueberries, and a buttery cinnamon topping.
It’s easy enough for an everyday treat but special enough to serve at brunch or share with friends. Enjoy a slice with coffee, pack a square for an afternoon snack, or warm it slightly for a cozy dessert.
Print
Oatmeal Blueberry Crumb Cake Recipe
- Total Time: 1 hour
- Yield: 9 squares 1x
- Diet: Vegetarian
Description
This Oatmeal Blueberry Crumb Cake is a soft, tender cake made with hearty oats and juicy blueberries, topped with a buttery cinnamon streusel. It’s a cozy homemade treat for breakfast, brunch, or dessert.
Ingredients
For the cake:
1 cup old-fashioned rolled oats
1 cup milk
1 1/2 cups all-purpose flour
1 1/2 teaspoons baking powder
1/2 teaspoon baking soda
1/4 teaspoon salt
1/2 teaspoon ground cinnamon
1/2 cup (113 g) unsalted butter, softened
3/4 cup (150 g) granulated sugar
1 large egg
1 teaspoon vanilla extract
1 1/2 cups blueberries
For the crumb topping:
1/2 cup all-purpose flour
1/2 cup old-fashioned rolled oats
1/2 cup (100 g) brown sugar
1/2 teaspoon ground cinnamon
1/4 cup (57 g) unsalted butter, melted
Instructions
1. Add the rolled oats and milk to a bowl. Stir and let sit for about 15 minutes.
2. Preheat the oven to 350°F (175°C). Grease or line an 8-inch square baking pan with parchment paper.
3. In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon.
4. In a large bowl, beat the softened butter and granulated sugar until light and creamy.
5. Add the egg and vanilla extract and beat until combined.
6. Stir the soaked oats and milk mixture into the butter mixture.
7. Add the dry ingredients and mix just until no dry flour remains.
8. Gently fold in the blueberries.
9. To make the crumb topping, combine the flour, oats, brown sugar, and cinnamon in a separate bowl.
10. Pour in the melted butter and mix with a fork until coarse crumbs form.
11. Spread the cake batter evenly into the prepared pan.
12. Sprinkle the crumb topping evenly over the batter.
13. Bake for 35–45 minutes, or until the top is golden and a toothpick inserted into the center comes out clean or with a few moist crumbs.
14. Cool in the pan on a wire rack for at least 20 minutes before slicing.
Notes
Soak the oats in milk before mixing the batter for a tender texture.
If using frozen blueberries, add them directly from the freezer without thawing.
Fold the blueberries gently into the batter to avoid crushing them.
If the crumb topping browns too quickly, loosely cover the pan with foil near the end of baking.
Store covered at room temperature for up to 2 days, refrigerate for up to 5 days, or freeze for up to 2 months.
- Prep Time: 20 minutes
- Cook Time: 40 minutes
- Category: Breakfast, Dessert
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 square
- Calories: 365
- Sugar: 29 g
- Sodium: 250 mg
- Fat: 16 g
- Saturated Fat: 9 g
- Unsaturated Fat: 6 g
- Trans Fat: 0 g
- Carbohydrates: 52 g
- Fiber: 3 g
- Protein: 5 g
- Cholesterol: 55 mg
Gianna Poulef
I’m Gianna Poulef from Poulef Recipes. I love sharing perfected dishes from my kitchen. I’m sure they’ll earn a spot in your heart. Let’s savor this journey together!.
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