Butternut Squash & Bacon Breakfast Casserole with spinach and chives is a cozy, flavorful way to start the day. This straightforward, egg-based casserole works well for family mornings, brunch gatherings, or as a make-ahead option during colder months. It balances roasted squash sweetness with salty bacon, bright herbs, and tender eggs for a dish that’s filling and easy to scale.
I created this version after seeing a great response to a similar sweet potato, sausage, and kale casserole. The formula for an egg casserole is simple: seasonal vegetables, a preferred breakfast meat if you like it, a few herbs, and plenty of beaten eggs. With that base you can vary cheeses, herbs, and leafy greens to suit tastes and dietary needs.
This particular casserole features butternut squash because I enjoy the texture and subtle sweetness of winter squash. I pair it with bacon, dried oregano, and fresh chives, and top the dish with aged white cheddar. If you prefer, substitute mozzarella or omit cheese entirely to make it dairy-free.
How to Make the Breakfast Casserole
Start by cooking thick-cut bacon in a large skillet over medium-high heat until much of the fat has rendered and the bacon reaches your preferred crispness. Transfer the cooked bacon to a cutting board to cool, leaving the bacon fat in the skillet to cook the squash for added flavor.
Add the peeled, chopped butternut squash to the skillet and cover. Cook until the squash has softened but still has a little bite, about 3–4 minutes, then remove the cover. Add the baby spinach and continue to cook, stirring occasionally, until the spinach wilts. Stir in dried oregano and chopped chives, then chop and return the bacon to the pan and mix everything together.
Whisk the eggs in a bowl until smooth and slightly frothy. Preheat the oven to 375°F (190°C) and lightly oil a large casserole dish. Transfer the cooked vegetable and bacon mixture to the prepared dish, pour the beaten eggs over the top, and use a spoon to distribute the vegetables evenly. Sprinkle the cheese across the casserole if using.
Bake on the center rack for 45–55 minutes, until a knife inserted near the center comes out clean and the eggs are set. Allow the casserole to rest for 10–15 minutes before slicing — this helps it hold together and makes serving easier. Top with extra chopped chives, a dollop of plain or coconut milk yogurt, sour cream, sliced avocado, or hot sauce to taste.
Recipe Adaptations and Tips
- Cheese swap: use mozzarella, gouda, or omit cheese to make it dairy-free and Whole30-friendly.
- Herbs: fresh oregano, thyme, or sage all complement butternut squash; add them to taste.
- Meat alternatives: replace bacon with turkey chorizo, breakfast sausage, or omit for a vegetarian version.
- Greens: substitute kale or collard greens for spinach; if using tougher greens, sauté a bit longer to soften.
- Make-ahead: assemble the casserole the night before and refrigerate; bake in the morning, or bake fully then refrigerate and reheat slices throughout the week.
- Storage & reheating: store leftovers covered in the refrigerator for 3–4 days. Reheat individual portions in a 350°F oven until warmed through, or microwave briefly for convenience.
- Slicing tip: let the casserole rest 10–15 minutes after baking so pieces hold their shape when cut.
I like serving the casserole with a spoonful of coconut milk yogurt and extra chives for brightness. Other excellent toppings include sour cream, thinly sliced red onion, diced avocado, or a few dashes of hot sauce. This dish is especially handy during the holiday season and colder months because it feeds a crowd and reheats well for busy weekday breakfasts.
Butternut Squash & Bacon Breakfast Casserole
Ingredients
- 5 strips thick-cut bacon (about 5 ounces)
- 3 cups butternut squash, peeled and chopped
- 4 cups baby spinach
- 1 Tbsp dried oregano
- 1/2 cup chives, chopped
- 2 tsp sea salt
- 18 large eggs
- 2 cups aged white cheddar, or mozzarella (optional)
Instructions
- Preheat the oven to 375°F and lightly coat a large casserole dish with avocado oil or olive oil.
- Cook the bacon in a large skillet over medium-high heat, flipping every 2–3 minutes, until much of the fat has rendered and the bacon is cooked to your liking. Transfer the bacon to a cutting board and reduce skillet heat to medium.
- Add the chopped butternut squash to the skillet, cover, and cook for about 3 minutes, stirring occasionally. Remove the cover and add the spinach. Cook, stirring occasionally, until the spinach has wilted, about another 2–3 minutes.
- Stir in oregano, chives, and sea salt. Chop the bacon and add it to the mixture. Transfer everything to the prepared casserole dish.
- Whisk the eggs in a mixing bowl until creamy. Pour the beaten eggs over the vegetables and gently stir to distribute evenly. Sprinkle the cheese across the top if using.
- Bake on the center rack for 45–55 minutes, until a knife inserted near the center comes out clean. My casserole usually takes about 50 minutes.
- Allow the casserole to cool for 10–15 minutes before slicing. Serve with yogurt, sour cream, chopped chives, or your preferred toppings.
Nutrition
Serving: 1 of 12 — Calories: 209 kcal; Carbohydrates: 9 g; Protein: 19 g; Fat: 11 g; Saturated Fat: 5 g; Polyunsaturated Fat: 3 g; Cholesterol: 297 mg; Fiber: 3 g; Sugar: 4 g
Nutrition information is an approximation and should be used as a guide only.
This butternut squash and bacon casserole is adaptable, satisfying, and designed to be stress-free. Whether you’re feeding guests or prepping breakfasts for the week, it holds up well and freezes nicely in portions. Enjoy customizing it to your tastes and seasonal produce.