Pin it The morning sunlight was barely creeping through my kitchen window when I decided to throw together whatever I had in the fridge. Sweet potatoes were sitting on the counter, looking a bit lonely next to a carton of eggs. I honestly had no grand plan until that first whiff of onions hitting hot olive oil changed everything.
My sister was visiting from out of town and looked skeptically at the sweet potatoes in my breakfast casserole. By the time she took her third bite, she was already asking for the recipe. Now she texts me every time she makes it, usually with some variation she discovered on her own.
Ingredients
- 3 medium sweet potatoes, peeled and diced: These become the heart of the dish, naturally sweet and creamy when baked. I learned the hard way that 1 inch cubes cook evenly, so aim for consistent sizing.
- 1 small yellow onion, finely chopped: The onion provides that essential savory base. Crying while chopping is practically guaranteed, but the flavor payoff is worth every tear.
- 1 red bell pepper, diced: This adds a pop of color and subtle sweetness. Any color works in a pinch, but red brings the prettiest contrast against the orange sweet potatoes.
- 2 cups baby spinach, roughly chopped: The spinach wilts down beautifully, sneaking in some greens without overwhelming the dish. Fresh is best here, frozen gets too watery.
- 8 large eggs: The binding magic that pulls everything together into custardy perfection. Room temperature eggs incorporate more smoothly into the milk mixture.
- 1 cup milk: Creates that tender, creamy texture we all want in a breakfast casserole. I have used everything from whole milk to almond milk with success.
- 1 cup shredded cheddar cheese: Sharp cheddar gives you the best flavor punch here. Pre shredded works, but grating your own melts better.
- 1/2 cup crumbled feta cheese: Totally optional but I am personally obsessed with the salty tang it brings to each bite. If you skip it, maybe add a pinch more salt to the egg mixture.
- 2 tablespoons olive oil: For sautéing those vegetables until they are perfectly tender. Butter works too, but olive oil handles the heat without burning.
- 1 teaspoon salt: Enhances all the flavors without making it taste salty. Trust me, sweet potatoes need a good amount to shine.
- 1/2 teaspoon black pepper: Adds a gentle warmth that balances the sweet elements. Freshly cracked pepper makes a noticeable difference.
- 1/2 teaspoon smoked paprika: This is the secret ingredient that makes people ask what you added. It brings this incredible depth without any actual heat.
- 1/4 teaspoon garlic powder: Rounds out the savory notes without the raw bite of fresh garlic. Powder distributes more evenly throughout the egg mixture.
Instructions
- Preheat your oven:
- Set it to 375°F and grab a 9x13 inch baking dish. A quick spray of cooking oil or a light butter coating prevents sticking later.
- Sauté the vegetables:
- Heat olive oil in a large skillet over medium heat. Toss in the sweet potatoes and onion, letting them cook for about 8 minutes until the potatoes are just tender when pierced with a fork.
- Add the remaining vegetables:
- Stir in the bell pepper for 3 more minutes, then add the spinach until it wilts down completely, about 1 minute. Remove everything from the heat.
- Layer the vegetables:
- Spread your cooked vegetables evenly across the prepared baking dish. Take your time here to distribute them well for consistent bites.
- Whisk the egg mixture:
- In a large bowl, beat the eggs with milk, salt, pepper, smoked paprika, and garlic powder. Whisk until completely combined and slightly frothy.
- Combine and cheese:
- Pour the egg mixture over the vegetables, letting it settle into all the nooks and crannies. Sprinkle cheddar and feta evenly across the top.
- Bake until set:
- Slide the dish into the oven for 30 to 35 minutes. The center should be just set with a slight wobble, and the top should be golden brown.
- Rest before serving:
- Let the casserole cool for 5 minutes. This patience pays off with cleaner slices and keeps the cheese from sliding right off.
Pin it 
Pin it This casserole has become my go to for holiday mornings and casual brunches alike. Something about gathering around a dish that took actual effort but still feels homey and unpretentious.
Make It Ahead
Assemble everything the night before and refrigerate covered. You may need to add a few extra minutes to the baking time since it will start cold.
Vegetable Swaps
Kale holds up beautifully if you want something heartier than spinach. Diced mushrooms or zucchini work well too, just cook them down a bit longer in the skillet.
Serving Suggestions
A simple green salad with vinaigrette cuts through the richness nicely. Crusty bread for soaking up any runny edges is never a bad idea.
- Hot sauce on the table for those who like a morning kick
- Fresh fruit on the side adds brightness to the plate
- Coffee or mimosas complete the brunch experience perfectly
Pin it 
Pin it There is something deeply satisfying about a breakfast that feeds a crowd and leaves everyone asking for seconds. Hope this finds its way into your regular rotation.
Recipe FAQs
- → Can I make this ahead of time?
Yes, you can assemble the entire casserole the night before and refrigerate it, covered. In the morning, let it sit at room temperature for 20 minutes while the oven preheats, then bake as directed. You may need to add a few extra minutes to the baking time if it's cold from the refrigerator.
- → How do I store leftovers?
Store cooled portions in an airtight container in the refrigerator for up to 4 days. Reheat individual slices in the microwave for 1-2 minutes or in a 350°F oven until warmed through. The texture remains excellent after reheating.
- → Can I freeze this casserole?
Absolutely. Bake the casserole completely, cool, then wrap tightly in plastic and foil. Freeze for up to 3 months. Thaw overnight in the refrigerator before reheating at 350°F for about 20 minutes.
- → What vegetables can I substitute?
Kale or Swiss chard work well in place of spinach. You can also add diced zucchini, mushrooms, or swap the bell pepper for poblano peppers if you enjoy mild heat. The key is maintaining a similar total volume of vegetables.
- → Is this suitable for meal prep?
Perfect for meal prep. Portion into individual containers after cooling completely. Each portion reheats beautifully in the microwave, making weekday breakfasts effortless. The flavors actually develop and improve after a day or two in the refrigerator.
- → Can I make this dairy-free?
Yes, use your favorite unsweetened non-dairy milk like almond or oat milk. For the cheese, either omit entirely or use a vegan cheddar alternative. The eggs naturally bind everything together, so it will still set properly without dairy.