High-Protein Breakfast Casserole

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This high-protein breakfast casserole is the best way to start your day, packed with eggs, cottage cheese and veggies. Cottage cheese adds a creamy texture and increases the protein content without overpowering the flavor. Earthy mushrooms, bell pepper and sautéed kale bring flavor to every bite. Enjoy it warm or reheat slices throughout the week for a satisfying, veggie-filled breakfast.

A slice of breakfast casserole with vegetables being served on a wooden spatula
Credit:

Photographer: Jen Causey, Food Stylist: Jennifer Wendorf, Prop Stylist: Hannah Greenwood.

Active Time:
25 mins
Total Time:
1 hr 15 mins
Servings:
6
  • Blending cottage cheese into the eggs creates a creamy custard-like texture while also adding protein. 
  • You can make this casserole ahead of time so it’s perfect for breakfasts throughout the week. 
  • This breakfast casserole is customizable and can be made with your favorite veggies.

This High-Protein Breakfast Casserole is the ultimate way to power up your morning, packed with a wholesome mix of eggs, creamy cottage cheese and hearty vegetables. The cottage cheese blends into the eggs, creating a rich, custard-like texture while adding a boost of protein. Baked until golden and set, this casserole is perfect for serving a hungry brunch crowd. While we enjoy the combination of antioxidant-rich veggies, this recipe is super versatile, so you can easily swap in your favorite produce. Read on for our expert tips and tricks below, from how to tell when the casserole is ready to ingredient swaps you can make. 

Tips from the EatingWell Test Kitchen

These are the key tips we learned while developing and testing this recipe in our Test Kitchen to make sure it works, tastes great and is good for you too! 

  • To distribute the vegetables evenly throughout the casserole, we add them in layers. Don’t worry if the second layer sinks into the eggs—they will settle in the middle of the casserole.
  • Precooking the vegetables develops their flavors and also releases moisture that would otherwise make the casserole watery. Mushrooms hold the most moisture, so we start them in the pan first.
  • At the end of cooking, your casserole should be puffed around the edges and golden brown. You can also jiggle the pan and see if the mixture is set in the center. When in doubt, you can always use an instant-read thermometer—eggs are fully cooked at 165°F.

Nutrition Notes

  • Eggs add protein to this hearty breakfast casserole to help you feel satiated, but that’s not all they deliver. They’re also packed with choline, a micronutrient that is crucial for memory, mood and nervous system function. 
  • Cottage cheese amps up the amount of protein, with a ½-cup serving contributing 12 grams of protein to the dish. Eating enough protein is important, as the nutrient plays a role in every function of the body, especially when it comes to muscle and digestive health. Cottage cheese also provides calcium and phosphorus for healthy bones. 
  • Mushrooms are a prebiotic food, so they work to feed the good bacteria in your gut, which can play an important role in overall health. The vegetable contains electrolytes like potassium to support lower blood pressure and blood glucose control. 
  • Kale contains antioxidants that may lower the risk of certain cancers, including those of the skin, breast and stomach. The dark leafy green also provides vitamin C, an essential vitamin that works to strengthen your immune system.
Ingredients for a breakfast casserole including eggs mushrooms spinach shredded cheese bell pepper and seasonings arranged on a surface

Photographer: Jen Causey, Food Stylist: Jennifer Wendorf, Prop Stylist: Hannah Greenwood.

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Ingredients

Original recipe (1X) yields 6 servings

  • 2 tablespoons extra-virgin olive oil, divided

  • 4 ounces sliced fresh wild mushrooms, such as oyster or shiitake (about 1 cup)  

  • 1 medium red bell pepper, chopped (about cups)

  • 1 small yellow onion, chopped (about 1 cup)

  • ¼ teaspoon salt, divided

  • 1 (5-ounce) package baby kale

  • teaspoons garlic powder

  • ¼ teaspoon crushed red pepper

  • 8 large eggs

  • ½ cup small-curd 2% reduced-fat cottage cheese

  • cup whole milk

  • cups shredded Colby-Jack cheese, divided

Directions

  1. Preheat oven to 350°F. Lightly coat an 8-inch-square baking dish with cooking spray.

  2. Heat 1 tablespoon oil in a large skillet over medium-high heat. Add 4 ounces sliced mushrooms; cook, undisturbed, until browned, about 4 minutes. Stir and continue to cook, stirring occasionally, until the moisture has evaporated, about 3 more minutes. Add chopped bell pepper, chopped onion, ⅛ teaspoon salt and the remaining 1 tablespoon oil; cook, stirring often, until softened, about 4 minutes. Add 5 ounces baby kale, 1½ teaspoons garlic powder and ¼ teaspoon crushed red pepper; cook and stir until the kale is wilted, about 2 minutes. Set aside to cool slightly, about 5 minutes.

    A skillet with cooked vegetables including spinach red peppers and mushrooms with a wooden spoon

    Photographer: Jen Causey, Food Stylist: Jennifer Wendorf, Prop Stylist: Hannah Greenwood.

  3. Combine 8 eggs, ½ cup cottage cheese, ⅓ cup milk, ¾ cup Colby-Jack and the remaining ⅛ teaspoon salt in a blender; process on low speed until smooth, about 20 seconds.

    Eggs and shredded cheese in a blender viewed from above prepared for a recipe

    Photographer: Jen Causey, Food Stylist: Jennifer Wendorf, Prop Stylist: Hannah Greenwood.

  4. Spread half of the kale mixture in the bottom of the prepared dish; pour the egg mixture over the top. Scatter the remaining kale mixture over the egg mixture (most of the vegetables will sink to the middle). Top with the remaining ¾ cup Colby-Jack. Bake until puffed around the edges and golden brown, about 40 minutes. Let stand for 10 minutes before serving.

    Vegetable casserole being prepared with a mixture poured into a baking dish containing spinach and vegetables

    Photographer: Jen Causey, Food Stylist: Jennifer Wendorf, Prop Stylist: Hannah Greenwood.

To make ahead

Let cool, then refrigerate in an airtight container for up to 3 days.

Frequently Asked Questions

  • What other vegetables can I use?

    Any vegetable will work well here, so long as it’s precooked to release moisture before it's mixed with the base. Spinach in place of kale is a good option to try, or swap in chopped broccoli or shredded Brussels sprouts.

  • What’s the best way to reheat this high-protein breakfast casserole?

    You can reheat individual slices in the microwave. Use short, 15- to 20-second intervals to keep the eggs from overheating and becoming rubbery.

  • Do I have to use a blender?

    We like how the blender seamlessly blends the eggs and cottage cheese together. You can whisk them together by hand, but the texture may not be as smooth.

Recipe developed by Marianne Williams

EatingWell.com, August 2025

Nutrition Facts (per serving)

310 Calories
21g Fat
11g Carbs
20g Protein
Nutrition Facts
Servings Per Recipe 6
Serving Size 1 (2⅔ -by-4-inch) piece
Calories 310
% Daily Value *
Total Carbohydrate 11g 4%
Dietary Fiber 2g 8%
Total Sugars 6g
Added Sugars 0g 0%
Protein 20g 40%
Total Fat 21g 27%
Saturated Fat 9g 44%
Cholesterol 278mg 93%
Vitamin A 350µg
Vitamin C 63mg 70%
Vitamin D 2µg
Vitamin E 2mg 15%
Folate 93µg
Vitamin K 172µg
Sodium 429mg 19%
Calcium 322mg 25%
Iron 2mg 12%
Magnesium 39mg 9%
Potassium 465mg 10%
Zinc 2mg 21%
Vitamin B12 1µg
Omega 3 0g

Nutrition information is calculated by a registered dietitian using an ingredient database but should be considered an estimate.

* Daily Values (DVs) are the recommended amounts of nutrients to consume each day. Percent Daily Value (%DV) found on nutrition labels tells you how much a serving of a particular food or recipe contributes to each of those total recommended amounts. Per the Food and Drug Administration (FDA), the daily value is based on a standard 2,000 calorie diet. Depending on your calorie needs or if you have a health condition, you may need more or less of particular nutrients. (For example, it’s recommended that people following a heart-healthy diet eat less sodium on a daily basis compared to those following a standard diet.)

(-) Information is not currently available for this nutrient. If you are following a special diet for medical reasons, be sure to consult with your primary care provider or a registered dietitian to better understand your personal nutrition needs.

Additional reporting by
Hilary Meyer
Hilary Meyer
Hilary Meyer is a recipe developer, tester, and content creator. After graduating from culinary school, she started working the EatingWell Test Kitchen in 2006, developing and testing recipes.
and
Alex Loh
Square Headshot of Alex Loh
Alex Loh is EatingWell's food editor. As part of the food team, she creates healthy, delicious recipes for the EatingWell audience. Alex also writes informative food and cooking articles that range from how to store ground beef to the best picks from Trader Joe's. Alex conducts product and taste tests to find the best options, from salad spinners to salsas.
Sources
EatingWell is committed to using high-quality, reputable sources—including peer-reviewed studies—to support the facts in our articles. Read about our editorial policies and standards to learn more about how we fact check our content for accuracy.
  1. US Department of Agriculture. FoodData Central. Cheese, cottage, lowfat, 2% milkfat.