This high-protein apple cinnamon oat bake tastes like a cozy dessert but fuels you like a balanced breakfast. It’s simple to mix in one bowl, bakes up golden and fragrant, and slices beautifully for the week. Each portion is hearty, lightly sweet, and packed with protein to keep you full.

Make it on Sunday, and you’ve got breakfast or snacks ready to go. It also reheats well, so you’ll never be stuck rummaging for something quick.

Jump to Recipe Card

What Makes This Recipe So Good

Overhead shot of a freshly baked high-protein apple cinnamon oat bake in an 8x8 pan, edges lightly g

Meal-prep friendly: One pan, multiple servings, and no morning fuss.
High protein: Protein powder plus Greek yogurt or cottage cheese boosts satiety.
Balanced and satisfying: Carbs from oats and apples, protein for staying power, and healthy fats for flavor.
Flexible and forgiving: Works with dairy or dairy-free swaps, and different apples or add-ins.
Not too sweet: Lightly sweetened so it doesn’t taste like a dessert bomb first thing in the morning.

Ingredients

2 cups old-fashioned rolled oats
1 scoop (25–30 g) vanilla or unflavored whey or plant-based protein powder
1 1/2 teaspoons ground cinnamon
1/2 teaspoon baking powder
1/4 teaspoon fine salt
2 medium apples, peeled if you prefer, diced small (about 2 cups)
2 large eggs
1 cup unsweetened almond milk (or dairy milk)
1/2 cup plain Greek yogurt (or blended cottage cheese)
2–3 tablespoons maple syrup or honey (adjust to taste)
1 teaspoon vanilla extract
2 tablespoons melted coconut oil or butter
Optional add-ins: 2 tablespoons ground flax or chia seeds, 1/4 cup chopped walnuts or pecans, handful of raisins

How to Make It

Close-up plated slice of the apple cinnamon oat bake on a matte white plate, thick square with defin

Preheat and prep: Heat the oven to 350°F (175°C). Lightly grease an 8×8-inch baking dish or line with parchment.
Mix dry ingredients: In a large bowl, combine oats, protein powder, cinnamon, baking powder, and salt.
Stir well to evenly distribute the protein powder.
Add apples and extras: Fold in the diced apples and any optional nuts, seeds, or raisins.
Whisk wet ingredients: In another bowl, whisk eggs, milk, Greek yogurt, maple syrup, vanilla, and melted oil until smooth.
Combine: Pour the wet mixture over the dry ingredients. Stir until everything is moistened. The batter will be thick.
Bake: Spread into the dish and smooth the top.
Bake for 30–38 minutes, until set in the center and lightly golden on the edges.
Cool and slice: Let it cool for at least 10–15 minutes before slicing. It firms up as it rests.
Serve: Enjoy warm as is, or top with a dollop of yogurt, a drizzle of nut butter, or a splash of warm milk.

How to Store

Fridge: Store slices in an airtight container for up to 5 days.
Freezer: Wrap individual pieces and freeze for up to 2 months. Thaw overnight in the fridge.
Reheat: Microwave for 30–60 seconds or warm in a 300°F (150°C) oven for 8–10 minutes.

Why This is Good for You

Protein helps you stay full: The combo of protein powder and yogurt supports satiety and muscle repair.
Whole grains for steady energy: Oats deliver fiber and slow-release carbs to power your morning.
Micronutrient boost: Apples add vitamin C and additional fiber, especially if you keep the peel.
Balanced macros: Carbs, protein, and healthy fats work together to avoid mid-morning crashes.

Pitfalls to Watch Out For

Overbaking: This can dry it out.
Pull it when the center is just set.
Too much protein powder: Extra scoops can make it rubbery. Stick to one standard scoop.
Uneven mixing: If protein powder clumps, whisk it into the dry ingredients thoroughly before adding liquids.
Using instant oats: They can turn mushy. Old-fashioned rolled oats hold their texture best.

Variations You Can Try

Apple pie vibes: Add a pinch of nutmeg and allspice, plus a few raisins.
Dairy-free: Use plant-based protein, dairy-free yogurt, and non-dairy milk.
Extra fiber: Stir in ground flax or chia seeds.
Crunch factor: Sprinkle chopped walnuts or pecans on top before baking.
Lower sugar: Skip the syrup and use a few extra tablespoons of unsweetened applesauce.
No eggs: Replace eggs with 2 flax eggs (2 tablespoons ground flax + 6 tablespoons water, rested 10 minutes).

FAQ

Can I use steel-cut oats?

Steel-cut oats won’t soften properly in this recipe without pre-cooking.

Stick to rolled oats for best texture.

What kind of protein powder works best?

Whey blends bake well and stay tender. For dairy-free, use a neutral-tasting pea or plant blend; you may need a splash more milk if the batter is very thick.

Can I make it without sweetener?

Yes. Use sweeter apples like Honeycrisp or Fuji and add a bit more cinnamon.

A few raisins can also help if you want natural sweetness.

How many servings does this make?

An 8×8-inch pan makes 6–9 squares, depending on your preferred portion size.

How do I reheat it so it tastes fresh?

Warm a slice with a splash of milk in the microwave or oven to bring back moisture, then finish with yogurt or nut butter.

Can I bake it in muffin tins?

Yes. Grease or line a 12-cup muffin tin and bake about 18–22 minutes, checking for doneness at 18 minutes.

In Conclusion

This high-protein apple cinnamon oat bake is reliable, cozy, and practical for busy weeks. It’s simple to assemble, easy to customize, and satisfying without being heavy.

Make a pan once, and you’ll have a ready-to-go breakfast that actually keeps you full. Warm it up, add your favorite topping, and you’re set.