Ingredients:
- Day-old Sourdough Bread, 1 lb (450 g), cut into 1-inch cubes
- Unsalted Butter, 1 Tbsp (15 g), softened (for pan)
- Bulk Pork Sausage, 1 lb (450 g)
- Yellow Onion, 1 medium, finely diced
- Garlic, 2 cloves, minced
- Fresh Thyme leaves, 1 tsp, finely chopped
- Mature/Sharp Cheddar Cheese, 2 cups (225 g), grated, divided
- Large Eggs, 12
- Whole Milk, 1.5 cups (360 ml)
- Heavy Cream (Double Cream), 0.5 cup (120 ml)
- Dijon Mustard, 1 Tbsp (15 ml)
- Salt (Kosher or Sea), 1.5 tsp
- Freshly Ground Black Pepper, 0.5 tsp
- Pinch of Ground Nutmeg (Optional)
Instructions:
- Prep the bread: Cut the sourdough into 1-inch cubes. If the bread is very fresh, spread the cubes on a baking sheet and bake at 300°F (150°C) for 10–15 minutes until slightly dried out. Generously grease a 9x13 inch baking dish with softened butter.
- Brown the sausage: Cook the bulk pork sausage in a large skillet over medium-high heat until fully browned, breaking it up with a spoon. Drain off any excess grease and transfer the sausage to a separate bowl.
- Sauté aromatics: Reduce the heat to medium. Add the diced onion to the same skillet and cook until softened (5–7 minutes). Add the minced garlic and fresh thyme; cook for 1 minute until fragrant. Add the cooked sausage back to the skillet and season lightly with pepper.
- Whisk the custard: In a large mixing bowl, whisk together the 12 eggs until frothy. Gradually whisk in the whole milk, heavy cream, Dijon mustard, salt, pepper, and nutmeg (if using). Whisk until thoroughly combined.
- Layer the strata: Place half of the bread cubes evenly across the bottom of the prepared dish. Spoon the sausage and onion mixture evenly over the bread, and sprinkle with 1 cup of the grated cheddar cheese. Top with the remaining half of the bread cubes.
- Soak and chill: Slowly pour the entire egg custard evenly over the assembled layers, ensuring all the bread cubes are saturated. Press down gently. Cover the dish tightly and refrigerate for at least 4 hours, but ideally overnight (8–12 hours). This resting period is essential for a perfect texture.
- Preheat and prepare for baking: Preheat the oven to 375°F (190°C). Remove the casserole from the fridge 30 minutes before baking to take the chill off. Remove the plastic wrap/foil.
- Bake: Bake the casserole for 30 minutes. Remove it, sprinkle the remaining 1 cup of cheddar cheese over the top. Return to the oven and bake for an additional 25–30 minutes, or until the top is golden brown and a knife inserted near the center comes out clean (internal temperature 200°F/93°C).
- Rest and Serve: Allow the casserole to rest for 10–15 minutes before slicing and serving. This allows the internal structure to set fully.