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Lemon Protein Oatmeal Cake (Easy & Delicious 7-Ingredient Recipe!)

Lemon Protein Oatmeal Cake
Lemon Protein Oatmeal Cake

There’s something so uplifting about the scent of fresh lemons wafting through the kitchen! This Lemon Protein Oatmeal Cake is a perfect balance of zesty citrus flavor, natural sweetness, and wholesome ingredients. It’s light yet satisfying, packed with protein, and naturally gluten-free if you use certified oat flour.

Whether you’re looking for a nutritious breakfast option, a post-workout snack, or a guilt-free dessert, this cake fits the bill! It’s soft, moist, and bursting with bright lemon flavor—seriously, you’ll want a second slice. Let’s dive into the details!

Why You’ll Love This Lemon Protein Oatmeal Cake

High in protein – Thanks to the protein powder and eggs (or flax eggs for a vegan twist), this cake is a satisfying treat that keeps you energized

Naturally sweetened – No refined sugars here! Maple syrup or honey adds just the right amount of sweetness

Wholesome and gluten-free – Using oat flour makes this cake nutrient-dense while keeping it naturally gluten-free (if using certified GF oats)

Moist and fluffy – The combination of almond milk, eggs, and lemon juice keeps this cake delightfully soft

Vibrant lemon flavor – Fresh lemon zest and juice infuse every bite with a tangy brightness!

Ingredients You’ll Need

  • 1 ½ cups (150g) oat flour (blend rolled oats if needed)
  • ¼ cup (30g) vanilla protein powder
  • 1 tsp baking powder
  • ¼ tsp salt
  • ¼ cup (60ml) maple syrup (or honey)
  • 2 large eggs (or flax eggs for a vegan option)
  • ¾ cup (180ml) almond milk (or any milk of choice)
  • Zest of 1 lemon
  • ¼ cup (60ml) fresh lemon juice

Kitchen Tools You’ll Need

  • Mixing bowls
  • Whisk or electric mixer
  • Measuring cups & spoons
  • 8-inch (20cm) round or square baking dish
  • Parchment paper (optional, for easy removal)
  • Oven

How to Make Lemon Protein Oatmeal Cake

Step 1: Prep the Oven & Baking Dish

Preheat your oven to 350°F (175°C). Grease your baking dish lightly or line it with parchment paper for easy removal

Step 2: Mix the Dry Ingredients

In a large mixing bowl, whisk together the oat flour, protein powder, baking powder, and salt until well combined

Step 3: Combine the Wet Ingredients

In another bowl, whisk together the eggs, maple syrup, almond milk, lemon zest, and lemon juice until smooth. The lemon juice might slightly curdle the milk—that’s totally fine!

Step 4: Mix Everything Together

Gradually pour the wet ingredients into the dry ingredients, stirring gently until just combined. Avoid overmixing to keep the cake fluffy!

Step 5: Bake to Perfection

Pour the batter into your prepared baking dish and smooth the top. Bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean

Step 6: Cool & Enjoy!

Let the cake cool in the pan for about 10 minutes before transferring it to a wire rack. Slice and serve warm, or let it cool completely for a firmer texture

What to Serve with This Lemon Protein Oatmeal Cake

This cake is delicious on its own, but here are a few ways to make it even better

  • A drizzle of Greek yogurt & honey for extra protein and creaminess
  • Fresh berries like raspberries, blueberries, or strawberries
  • A dusting of powdered sugar for a touch of elegance
  • A dollop of almond or peanut butter for a heartier snack

Tips for the Best Lemon Protein Oatmeal Cake

Use fresh lemon juice & zest – The brightness of fresh citrus is key to this cake’s flavor

Don’t overmix the batter – Overmixing can make the cake dense instead of fluffy

Check for doneness early – Every oven is different, so start checking around 25 minutes

Adjust the sweetness – If you like a sweeter cake, add an extra tablespoon of maple syrup or honey

How to Store Your Lemon Protein Oatmeal Cake

Room temperature: Store in an airtight container for up to 2 days

Refrigerator: Keep in the fridge for 5-6 days

Freezer: Slice and freeze individual portions for up to 3 months. Simply thaw and enjoy!

Frequently Asked Questions

Can I make this cake vegan?

Yes! Just replace the eggs with flax eggs (2 tbsp ground flax + 6 tbsp water, let sit for 5 minutes)

What type of protein powder works best?

A vanilla plant-based or whey protein powder works great. If using unsweetened protein, you may want to add an extra tablespoon of maple syrup

Can I use a different flour?

Oat flour works best for texture, but almond flour can be used for a softer cake. Avoid coconut flour, as it absorbs too much liquid

How do I make this into muffins?

Simply pour the batter into lined muffin tins and bake at 350°F (175°C) for 15-18 minutes

More Delicious Recipes to Try

If you love this Lemon Protein Oatmeal Cake, check out these other wholesome treats!

Final Thoughts

This Lemon Protein Oatmeal Cake is proof that healthy can be delicious! It’s easy to make, packed with wholesome ingredients, and full of zesty lemon goodness. Whether you’re enjoying it for breakfast, a snack, or dessert, this cake will brighten your day

If you try this recipe, let me know in the comments or tag me in your photos on Pinterest—I’d love to see your creations!

Happy baking! 🍋✨

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Lemon Protein Oatmeal Cake
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Lemon Protein Oatmeal Cake – A Bright & Nourishing Treat!


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  • Author: Poulef
  • Total Time: 35 minutes
  • Yield: 8 servings 1x
  • Diet: Gluten Free

Description

This Lemon Protein Oatmeal Cake is light, moist, and packed with protein! Made with wholesome oat flour, zesty lemon, and natural sweeteners, it’s a perfect balance of flavor and nutrition. Whether you need a healthy breakfast, a post-workout snack, or a guilt-free dessert, this cake has you covered. Naturally gluten-free and easy to make, you’ll love every bite of this energizing treat!


Ingredients

Scale
  • 1 ½ cups (150g) oat flour (blend rolled oats if needed)

  • ¼ cup (30g) vanilla protein powder

  • 1 tsp baking powder

  • ¼ tsp salt

  • ¼ cup (60ml) maple syrup (or honey)

  • 2 large eggs (or flax eggs for vegan option)

  • ¾ cup (180ml) almond milk (or any milk of choice)

  • Zest of 1 lemon

  • ¼ cup (60ml) fresh lemon juice


Instructions

  • To make this cake vegan, use flax eggs (2 tbsp ground flax + 6 tbsp water, let sit for 5 minutes).

  • If using an unsweetened protein powder, you may want to add an extra tablespoon of maple syrup for sweetness.

  • For a stronger lemon flavor, add an extra teaspoon of lemon zest.

  • Store at room temperature for 2 days, in the fridge for 5-6 days, or freeze for up to 3 months

Notes

To make this cake vegan, use flax eggs (2 tbsp ground flax + 6 tbsp water, let sit for 5 minutes).

If using an unsweetened protein powder, you may want to add an extra tablespoon of maple syrup for sweetness.

For a stronger lemon flavor, add an extra teaspoon of lemon zest.

Store at room temperature for 2 days, in the fridge for 5-6 days, or freeze for up to 3 months.

  • Prep Time: 10
  • Cook Time: 25
  • Category: Breakfast, Snack, Dessert
  • Method: Baking
  • Cuisine: Healthy
Product Image

26-Piece Stainless Steel Mixing Bowls Set

A versatile set of mixing bowls with airtight lids and non-slip bottoms. Includes 3 grater attachments for added convenience in the kitchen!

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I’m 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!. Let’s be friends!