Ingredients:

  • 1 lb (450 g) day-old sourdough bread, cut into 1-inch cubes
  • 1 Tbsp (15 g) unsalted butter
  • 1 lb (450 g) bulk breakfast sausage
  • 1 medium (150 g) yellow onion, finely diced
  • 2 cloves garlic, minced
  • 8 oz (225 g) mature cheddar cheese, grated (divided)
  • 12 large eggs, whisked
  • 2 cups (480 ml) whole milk
  • 1 cup (240 ml) double cream (heavy cream)
  • 1 Tbsp (15 ml) Dijon mustard
  • 1 tsp (5 ml) Worcestershire sauce
  • 5 tsp (7.5 g) kosher salt
  • 5 tsp (2.5 g) freshly ground black pepper
  • 1 pinch (1 g) ground nutmeg
  • 1 Tbsp (5 g) fresh chives, finely chopped (optional, for garnish)

Instructions:

  1. Prep the Dish and Bread: Lightly butter or grease a 9x13 inch baking dish. Cut the stale sourdough into roughly 1-inch cubes and set aside.
  2. Cook the Meat: Heat a large skillet over medium heat. Add the sausage meat and break it up, cooking until browned (about 5–7 minutes). Drain off excess fat, leaving about 1 tablespoon in the pan.
  3. Sauté Aromatics: Add the diced onion to the skillet and cook until softened (about 3 minutes). Stir in the minced garlic for the last minute. Remove the mixture from heat.
  4. Layer the Bread and Filling: Spread the cubed sourdough evenly across the bottom of the prepared baking dish. Sprinkle the cooked sausage, onion, and garlic mixture evenly over the bread. Top with 6 oz (170g) of the grated cheddar cheese, reserving the remaining 2 oz for the topping.
  5. Mix the Custard: In a large bowl, whisk the eggs thoroughly. Gradually whisk in the whole milk, double cream, Dijon mustard, Worcestershire sauce, salt, pepper, and nutmeg until well combined and frothy.
  6. Soak and Chill: Pour the entire custard mixture evenly over the bread and filling, ensuring all the bread is thoroughly saturated. Gently press down on the bread cubes. Cover the dish tightly with plastic wrap and refrigerate for a minimum of 4 hours, or ideally overnight (8–12 hours).
  7. Preheat and Temper: Preheat the oven to 375°F (190°C). Remove the casserole from the refrigerator 30 minutes before baking to allow it to come slightly closer to room temperature.
  8. Initial Bake: Remove the plastic wrap. Bake the casserole, uncovered, for 30 minutes.
  9. Add Cheese and Finish: Sprinkle the reserved 2 oz (55g) of cheddar over the top. Return the casserole to the oven and continue baking for another 20–25 minutes, or until the top is golden brown and a knife inserted near the center comes out clean.
  10. Rest and Serve: Remove from the oven and allow to rest for 10 minutes before slicing and serving. Garnish with fresh chives, if using.