Zucchini and Apple Protein Oat Bake

Oatmeal bakes are an easy, healthy breakfast meal prep. This zucchini and apple protein oat bake is made with fresh vegetables, apples, spices, greek yogurt, vanilla protein powder, and eggs. It can be served warm or cold, and is a nutritious and filling way to start your morning.

If there is one food I could eat every day for the rest of my life it would be oatmeal. I can eat it hot, cold, in baked goods, or in granola.

Over the summer on my bachelorette weekend, my friend Katherine made this phenomenal apple oatmeal bake to share with us. I love apples as much as I love oatmeal, so needless to say I was in heaven. The texture was so tender, light, but also filling enough to make a meal out of it. We ate it warm, but I ate it cold the next day and it was just as good!

I wanted to recreate something similar to the oatmeal bake she made. I was on a zucchini kick, and so I created a recipe that I could turn into a more zucchini-bread version.

What is an Oatmeal Bake?

If you’ve never had an oatmeal bake before, it’s essentially a breakfast casserole made with old fashioned rolled oats, eggs, spices, often milk and other pantry ingredients. The texture is similar to a bread pudding, but it’s more light, chewy and soft. Oatmeal bakes are so customizable and easy to throw together in one pan.

Best of all, oatmeal bakes can be made in advance for meal prep or a healthy snack. Oatmeal bakes are NOT oat bars, so you will need a fork or spoon to eat it.

Ingredients in Zucchini and Apple Protein Oatmeal Bake

Old Fashioned Rolled Oats – Don’t substitute steel cut oats or quick cook. Steel cut would turn out very chewy, and quick cook oats likely would be too mushy.
Shredded Zucchini – The best way to shred zucchini for this recipe is with a grater. No need to drain the zucchini, but if you think it’s got extra liquid you could pat it dry. A medium sized zucchini is all you need.
Apple – I use a nice fresh Honeycrisp apple. A Pink Lady apple could work well too. Dice the apple small.
Greek Yogurt – I use whole milk Greek yogurt. This adds a boost of protein and extra creaminess.
Almond Milk – Or any milk of your choice. I prefer almond or oat milk.
Eggs – This recipe calls for two large eggs.
Maple Syrup – You can substitute honey.
Unsweetened Apple Sauce – This brings a natural sweetness to the oats that I love.
Vegetable Oil – I use a bit of vegetable oil for added moisture. You could also use another neutral oil like canola oil.
Vanilla Protein Powder – Any vanilla whey protein works great here. I rotate the protein powders I use, but Pure Protein powder or Dymatize protein powder are two of my favorites.
Baking Powder – A chemical leavening agent.
Spices – I use ground cinnamon and ginger, but you can get creative and add a pinch of nutmeg or whatever other spices you enjoy.
Vanilla Extract – Vanilla enhances the spices and sweetness.
Lemon Zest – Zest adds such a lovely balance to the recipe and brightens it up.
Ground Flaxseed – Flaxseed has healthy benefits including omega-3s fatty acids and protein. It is optional.
Optional Mix-Ins – Toasted walnuts or pecans, chia seeds, pumpkin seeds, sunflower seeds, shredded coconut, a few tablespoons of chopped dried fruit. I love changing it up!

Substitutions, Modifications and Questions

How do I know when it is done? The edges will be brown, and the center will be set. Use a toothpick and make sure it comes out clean.
Can I substitute lemon zest for lemon juice? Yes, use two tablespoons of lemon juice instead of the zest.
Can I make this vegan? I have not tried this as a vegan recipe. In theory, you could substitute the eggs for “flaxseed eggs.” You could swap the Greek yogurt for non-dairy yogurt. I cannot speak to how the texture might be affected.
Can I leave out the protein powder? If you omit the protein powder, I suggest adding another quarter cup of oats or oat flour. You may also want to add another tablespoon or two of maple syrup to taste for added sweetness.
Can I use another flavor of protein powder? I would recommend vanilla or a similar flavor (maybe cinnamon?). Any flavor besides vanilla is going to alter the recipe slightly.

How to Store Apple and Zucchini Protein Oat Bake

This recipe can be kept in an airtight container in the refrigerator for up to 4 to 5 days. You can eat it cold (I like mine with a dollop of full fat Greek yogurt), or hot. You can reheat individual portions in the microwave for 30 seconds or in the toaster at 350 degrees Fahrenheit for 5 to 10 minutes.

If you need to reheat the whole pan, bake it for 15-20 minutes at 350 degrees Fahrenheit or until warmed.

Freezing Instructions

To freeze the oat bake, I like to wrap individual slices of the oatmeal bake tightly in plastic wrap and then in aluminum foil. Alternatively, you can wrap the oatmeal bake slices in plastic wrap and then store in a freezer gallon-size bag. When you wrap slices individually (or in pairs) it makes it easier to pull out a few at a time to eat. Just let them defrost in the refrigerator.

If you’re refreezing the whole pan, wrap it tightly in plastic wrap and then again with aluminum foil. Allow it to come to defrost in the refrigerator overnight and then bake it at 350 degrees Fahrenheit for 15-20 minutes until warm.

Looking for Other Oatmeal-Based Recipes?

If you love zucchini and oatmeal as much as I do, check out my zucchini overnight oats.