20 ounces sweet Italian sausage, casings removed if in links
1 tablespoon butter
1 medium onion, chopped into 1/2-inch pieces (about 1 cup)
8 ounces cremini mushrooms, cleaned, sliced
1 red bell pepper, diced
1 tablespoon chopped fresh thyme, optional
1 cup heavy whipping cream
1/2 cup half-and-half
10 eggs
1 teaspoon salt
1/2 teaspoon freshly ground black pepper
16 ounces egg bread or country bread (preferably 1 to 2 days old), cut into 1/2-inch-thick slices
2 1/2 cups shredded Fontina or Swiss cheese
Butter the bottom and sides of a 9-by-13-inch baking dish.
In a large skillet over medium heat, break up sausage and sauté until golden brown, about 10 to 12 minutes. Remove from heat and set aside on paper towel to drain. Add the 1 tablespoon butter to the same skillet and melt. Add the onions, mushrooms and bell pepper and sauté until they are tender. Remove from the heat and cool.
In a medium bowl, whisk the thyme if using with the cream, half-and-half, eggs, salt and pepper, and set aside.
Lay half of the bread in the buttered baking dish, sprinkle with half of the sausage mixture, half of the mushroom mixture and about half of the cheese. Repeat layering with remaining bread, sausage, mushroom and cheese. Slowly pour egg mixture over top. Press down on the bread so it gets covered with the egg mixture. Cover and refrigerate 30 minutes or overnight.
Preheat the oven to 350 degrees. Remove the strata from the refrigerator while the oven is preheating. Uncover and place the baking dish on a baking sheet to catch overflow. Bake 40 minutes, or until golden brown. Allow to sit 10 minutes before serving.
