Cheddar Bacon Breakfast Strata with Caramelized Onions

Why You’ll Love This Recipe

• All the brunch favorites—cheddar, bacon, and caramelized onions—baked into one cozy, crowd-pleasing casserole.
• Custardy inside, golden and crunchy on top for the perfect texture contrast.
• Flexible: assemble the night before for stress-free mornings.
• Foolproof layering method ensures every bite has bacon, onion, and melty cheese.

Grocery List

• Produce: 2 large yellow onions, 2 cloves garlic, fresh thyme (or dried), chives or scallions
• Dairy: 8 large eggs, whole milk, half-and-half, sharp cheddar, unsalted butter
• Pantry: Country bread loaf, thick-cut bacon, Dijon mustard, olive oil, kosher salt, black pepper, sugar

Full Ingredients

Bread and Fillings

• 10 cups day-old country or sourdough bread, cut into 1-inch cubes (12–14 oz)
• 10 oz thick-cut bacon, cut into 1/2-inch pieces
• 2 tbsp unsalted butter
• 1 tbsp olive oil
• 2 large yellow onions (about 1 1/2–2 lb), thinly sliced
• 1/2 tsp kosher salt (for onions)
• 1/2 tsp granulated sugar
• 2 cloves garlic, minced
• 1 tsp fresh thyme leaves, chopped (or 1/2 tsp dried thyme)
• 8 oz sharp cheddar, shredded (about 2 cups)

Custard

• 8 large eggs
• 2 cups whole milk
• 1 cup half-and-half
• 1 tbsp Dijon mustard
• 1 tsp kosher salt
• 3/4 tsp freshly ground black pepper

To Finish

• 2 tbsp chopped fresh chives or thinly sliced scallions
• Optional: hot sauce for serving

Step-by-Step Instructions

Step 1: Prep the pan and dry the bread

Heat the oven to 350°F. Grease a 9×13-inch baking dish with a little butter or nonstick spray. Spread the bread cubes on a sheet pan and toast for 10–12 minutes, stirring once, just until the surface feels dry. This helps the bread soak up the custard without turning soggy. Cool slightly while you prepare the fillings.

Step 2: Cook the bacon

Place the chopped bacon in a large skillet over medium heat. Cook, stirring occasionally, until the fat renders and the bacon is crisp, 8–10 minutes. Transfer the bacon to a paper-towel-lined plate. Pour off all but 1 tablespoon of bacon drippings from the skillet.

Step 3: Caramelize the onions

Add the butter and olive oil to the skillet with the reserved drippings. Stir in the onions, 1/2 teaspoon kosher salt, and the sugar. Cook over medium to medium-low heat, stirring occasionally, until the onions are deep golden and jammy, 18–22 minutes. If the pan browns too quickly, lower the heat and splash in 1–2 tablespoons of water to loosen the fond. Stir in the garlic and thyme and cook 1 minute more. Remove from the heat and cool 5 minutes.

Step 4: Whisk the custard

In a large bowl, whisk the eggs until blended. Add the milk, half-and-half, Dijon, 1 teaspoon kosher salt, and 3/4 teaspoon black pepper. Whisk until smooth and well combined.

Step 5: Layer the strata

Scatter half the toasted bread into the prepared baking dish. Top evenly with half the caramelized onions, half the bacon, and half the cheddar. Repeat with the remaining bread, onions, bacon, and cheddar. Slowly pour the custard over the entire dish, moving around so it soaks evenly. Gently press the top with the back of a spatula to help the bread absorb the custard. Cover tightly with foil.

Step 6: Soak briefly, then bake

Let the strata rest at room temperature for 15–30 minutes to begin absorbing, or refrigerate up to overnight for maximum custardiness. When ready to bake, keep the oven at 350°F. Bake covered for 30 minutes. Uncover and continue baking 18–25 minutes, until the top is golden-brown and the center feels set (an instant-read thermometer should read 165°F in the middle).

Step 7: Rest, garnish, and serve

Let the strata rest for 10–15 minutes so the custard finishes setting and slices cleanly. Sprinkle with chives or scallions. Cut into squares and serve warm, with hot sauce on the side if you like.

Pro Tips

• Use day-old bread or lightly toast fresh bread so the custard absorbs without making the strata mushy.
• Shred your own cheddar for the best melt and flavor; pre-shredded cheese has anti-caking agents.
• Press the top gently after pouring the custard to ensure every cube gets soaked.
• For a super-clean slice, let the baked strata rest the full 15 minutes before cutting.
• If the top browns too fast, tent loosely with foil for the last 10 minutes.

Variations

• Spinach-Mushroom: Sauté 8 oz sliced cremini and 5 oz baby spinach; layer with the onions. Swap half the cheddar for Gruyère.
• Green Chile-Jack: Replace cheddar with pepper jack and add 1 cup chopped roasted green chiles. Sprinkle with cilantro instead of chives.
• Everything Bagel Twist: Use cubed everything bagels for the bread and add 1 tablespoon everything bagel seasoning to the custard.

Storage & Make-Ahead

Assemble up to 24 hours ahead: cover and refrigerate, then bake as directed (add 5–10 minutes if it goes into the oven cold). Leftovers keep 3–4 days refrigerated; reheat covered at 325°F for 15–20 minutes or microwave individual portions. To freeze, bake, cool completely, wrap tightly, and freeze up to 2 months. Thaw overnight in the refrigerator, then reheat at 325°F until warmed through.

Nutrition (per serving)

Approximate: 480 calories; 25 g protein; 29 g carbohydrates; 30 g fat; 12 g saturated fat; 2 g fiber; 880 mg sodium.