Dinner

Vegetable Gruyère Bread Strata Recipe

ByNaomi Fletcher December 14, 2025December 14, 2025

Introduction

This Vegetable Gruyère Bread Strata is a warm, comforting dish perfect for brunch or a cozy dinner. Layered with sautéed vegetables, rich Gruyère cheese, and a custardy egg mixture, it’s both hearty and flavorful. Plus, it’s easy to prepare ahead and bake when ready.

A square piece of baked egg casserole sits on a white plate over a white marbled surface, showing three main layers: the bottom layer is a light, fluffy yellow egg base with small air pockets, the middle layer has dark green spinach pieces mixed with more eggs and diced red bell peppers, and the top layer is golden-brown with melted white cheese, scattered red pepper bits, and a sprinkle of finely chopped green herbs in the center, giving a fresh look. The background includes a white cup and saucer that are blurred. photo taken with an iphone --ar 4:5 --v 7

Ingredients

4 cups challah bread, cut into 1-inch cubes
1 tablespoon olive oil
1 medium onion, chopped
1 medium red bell pepper, chopped
2 cups fresh spinach, roughly chopped
1 ½ cups grated Gruyère cheese
6 large eggs
2 cups milk
½ teaspoon salt
¼ teaspoon black pepper
¼ teaspoon ground mustard

Instructions

Step 1: Preheat your oven to 350°F (180°C) and grease a 9×13 inch baking dish to prevent sticking.
Step 2: Heat the olive oil in a skillet over medium heat. Add the chopped onion and red bell pepper and cook until softened, about 5-7 minutes. Stir in the chopped spinach and cook until wilted, then remove from heat.
Step 3: In the prepared baking dish, arrange half of the challah bread cubes as the first layer. Spread the sautéed vegetable mixture evenly over the bread, then sprinkle half of the grated Gruyère cheese on top. Repeat with remaining bread, vegetables, and cheese.
Step 4: In a large bowl, whisk together the eggs, milk, salt, black pepper, and ground mustard until well combined. Pour the egg mixture evenly over the layered ingredients in the baking dish, pressing down gently to help the bread soak up the liquid.
Step 5: Cover the baking dish with foil and let it sit at room temperature for at least 30 minutes to allow the bread to absorb the custard.
Step 6: Bake covered for 30 minutes. Remove the foil and bake uncovered for an additional 25-30 minutes until the top is golden brown and the custard is set.
Step 7: Let the strata rest for 5-10 minutes before slicing and serving to help it firm up and make serving easier.

Tips & Variations

Use day-old or slightly stale challah bread for the best texture as it absorbs the custard without becoming too soggy.
Feel free to add other vegetables like mushrooms or zucchini for extra flavor and nutrition.
Substitute Gruyère with Swiss or mozzarella cheese if preferred.
For a make-ahead option, assemble the strata the night before, refrigerate, and bake the next day.

Storage

Store any leftovers in an airtight container in the refrigerator for up to 3 days. Reheat individual portions in the microwave or warm in a 350°F (175°C) oven until heated through.

How to Serve

A square piece of baked egg casserole sits on a white plate over a white marbled surface, showing three visible layers: the bottom layer is a light yellow, soft and fluffy baked mixture; the middle layer contains chunks of white cheese and colorful pieces of red and yellow bell peppers along with green spinach leaves; the top layer is golden brown with a slightly crispy texture and melted cheese mixed with more green spinach visible. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use a different type of bread?

Yes, brioche, French bread, or Italian bread can be good alternatives to challah. Just make sure the bread is slightly stale to absorb the custard well.

Can I make this strata vegan or dairy-free?

To make a vegan or dairy-free version, substitute eggs with a vegan egg replacement and use plant-based milk and cheese alternatives. The texture will be somewhat different but still tasty.