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The Best Breakfast Casserole Recipe If You're on the Keto Diet

Mushrooms, kale, and caramelized onions come together for a casserole you'll never tire of.

If you're following the keto diet, yes, you 100 percent can still enjoy a filling and flavorful meal to start your day. This breakfast casserole is the perfect way to change up the typical way to eat eggs. In this recipe, we combine mushrooms, baby kale, and caramelized onions in the egg-based casserole for a savory breakfast dish that takes just 35 minutes to cook, so you'll have a family-sized easy breakfast ready in no time.

What's great about this keto breakfast casserole is that you'll have plenty left over that you can easily reheat or even eat cold if you prefer. Meal-prepping for the week just got a whole lot easier and tastier for you.

Check out the full keto-friendly breakfast casserole recipe below.

Makes 8 servings


3 tbsp avocado oil or ghee
1 medium onion (11 oz), chopped (2 cups)
Fine sea salt and freshly ground black pepper
10 oz cremini mushrooms, thinly sliced (4 cups)
5 oz baby kale (about 4 cups), chopped
3 cloves garlic, minced (1 tbsp)
2 ¼ oz gruyere, shredded (¾ cup)
12 large eggs
1/2 cup heavy cream
2 tsp fresh thyme leaves
1 tbsp chopped fresh flat-leaf parsley

How to Make It

    1. Preheat oven to 350ºF; grease a 9-by-13-inch baking dish. Warm 1 tablespoon oil in a large skillet over medium heat. Add onion, sprinkle with salt, and cook, stirring occasionally, until golden and caramelized, about 10 to 12 minutes. Spread in baking dish. Warm 1 tablespoon oil in the same skillet. Add mushrooms, sprinkle with salt, and cook, stirring occasionally, until mushrooms release their water and are golden in color, about 10 to 12 minutes. Spread in baking dish.
    2. Add remaining 1 tablespoon oil, kale, and garlic to skillet and cook, stirring, until garlic is fragrant and the kale has wilted, about 2 to 3 minutes. Spread over mushroom mixture. Sprinkle with 1/2 cup gruyere.
    3. In a large bowl, beat eggs until well mixed. Beat in cream, thyme, and parsley, 1/2 teaspoon salt, and 1/4 teaspoon pepper. Pour over vegetables in baking dish. Sprinkle with remaining 1/4 cup cheese.
    4. Bake casserole until cooked through and edges are lightly golden, about 30 to 35 minutes. Let cool for 5 minutes before serving. Keep leftovers covered and refrigerated; rewarm slices in microwave or toaster oven, or serve cold.

RELATED: The easy way to make healthier comfort foods.

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Beth Lipton
Beth Lipton is a recipe developer and food writer. Read more