Name: Sourdough Breakfast Strata
Prep time: 15 min
Cook time: 50 min
Total time: 65 min
Ingredients: 1 pound sourdough bread (cut into 1-inch cubes); 2 tablespoons olive oil; 1 cup chopped yellow onion; 1 tablespoon dried thyme; 2 cloves fresh garlic (minced); sea salt and black pepper; 10 ounces baby spinach (or substitute chopped kale); 8 large eggs; 2.67 cups whole milk (I used unsweetened cashew milk (2 2/3 cup)); .25 teaspoon cayenne pepper* (or more to taste); 3 cups grated fontina cheese; 9 oil packed sun-dried tomatoes (diced); 0.5 cup grated Parmesan cheese; unsalted butter (to butter baking dish)

This post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases. For more information, please visit my disclosure page.

Jump to Recipe Print Recipe

Overnight Sourdough Breakfast Strata filled with eggs, milk, spinach, Italian fontina cheese, and sun-dried tomatoes is the perfect recipe for family brunch or dinner.

Sourdough Breakfast Strata with spinach and sun-dried tomatoes in a baking dish.

We all have comfort foods, right? For me, that would be fresh, tangy sourdough bread that has been grilled for sandwiches or baked into this delicious breakfast strata.

It all started back when I was in college and I tried my first Frisco Burger, I was hooked on the unique flavor and texture of sourdough bread.

Sourdough Breakfast Strata with sun-dried tomatoes, spinach and fontina cheese is perfect for brunch!! cookingwithcurls.com

Images updated on March 28, 2022

Gourmet Tuna Sandwiches are my go-to quick and easy sandwich, but last weekend I wanted something hearty enough for breakfast or dinner. This amazingly delicious Sourdough Breakfast Strata is exactly what I was looking for!

Looking down on a Sourdough Breakfast Strata in a baking dish with a glass of orange juice and small bowl of parmesan cheese on the side.

It is also the perfect solution for Easter or Mother’s Day brunch! Once the prep is done the night before, you just have to pop it in the oven in the morning for a stress-free entrée. We all know how crazy holiday meals can get, right?

Ingredients needed:

Ingredients to make Sourdough Breakfast Strata.

Sourdough bread is the star of this dish. Use bread that is several days old, or leave it out on the counter for a couple of hours to dry out.
Eggs acts as a binder and when mixed together with the milk they create a delicious onion, garlic, and spinach filling with just a hint of cayenne.
Grated Fontina or Gruyère cheese add lots of cheesy flavor.

Be sure to check out the detailed printable recipe card below

How to make Sourdough Breakfast Strata

Cut bread into cubes and set aside to dry slightly. You want bite sized pieces about 1-inch square.

I just laid them out on the cutting board while I was preparing the filling.

In a large skillet, heat oil over medium heat. Add the onion and cook until softened, 3 to 4 minutes. Stir in the thyme and garlic.

Diced onion, garlic and dried thyme in a skillet.

Next, stir in half of the baby spinach.

Baby spinach leaves added to the onion mixture in a skillet.

Cook until spinach is wilted.

Cooked spinach leaves and diced onion in a skillet.

Now add remaining spinach. When spinach is completely wilted, remove from heat and allow to cool for 10 minutes.

In a large bowl, whisk together eggs, milk, and cayenne pepper.

Beaten eggs, milk, and cayenne pepper whisked together in a large bowl.

Stir in the spinach mixture, set aside.

Cooked spinach and onion mixture mixed with beaten egg mixture in a large bowl.

Butter the bottom and sides of a 9 x 13 inch baking dish. Spread half of the bread cubes across the bottom of the pan. Sprinkle with half of the Fontina cheese.

Grated cheese sprinkled over bread cubes in a buttered baking dish.

Pour half of the spinach and egg mixture over the bread cubes and cheese.

Half of the spinach and egg mixture poured over the bread cubes and shredded cheese in a baking dish.

Add the remaining bread cubes and cheese, then pour the remaining spinach and egg mixture over the top.

Press down on the strata to compress the ingredients and make sure the filling spreads across the bread cubes.

Sprinkle the chopped sun-dried tomatoes and Parmesan cheese over the top.

Sourdough bread cubes, spinach and egg mixture topped with grated parmesan cheese in a baking dish.

Cover with foil and place in the refrigerator for at least 8 hours.

Preheat oven to 350 degrees. Bake strata uncovered for 50 to 60 minutes, until golden brown and custard is set. Remove from oven and cool for 15 minutes before serving.

A slice of Sourdough Breakfast Strata on a plate with mixed fruit.

Make sure you grab an outside piece, the butter makes the edges extra crispy and buttery flavored. The center is cheesy and custardy (not sure that is a real word), and the entire strata is loaded with flavor from the spinach, onions, and tomatoes…Yum!

Tools used to create this recipe

You can see the rest of my favorite kitchen tools and gadgets here in my Amazon Affiliate Page. I earn a small commission when you purchase through my links, at no cost to you, so I can keep bringing you more delicious recipes!

More delicious sourdough recipes

Leftover sourdough also make delicious Crunchy Garlic Croutons as well!

You can see how much I love sourdough bread, how about you?

If you love this recipe, please rate it five stars and help me share on facebook and to help other readers in our community!

Enjoy!!