Ham and Cheese Croissant Bake

Bahan-bahan (6 porsi)

• 12 cups (about 12-16 croissants) roughly torn, day-old croissants
• 2 tablespoons salted butter, thinly sliced
• 2 tablespoons extra virgin olive oil
• 2 cups mixed mushrooms, roughly chopped
• kosher salt and pepper
• 2 cloves garlic, minced or grated
• 2 tablespoons fresh chopped thyme ((or 2 teaspoons dried thyme))
• 1 cup heavy cream
• 1 cup whole milk
• 3 large eggs, beaten
• 2 rounded tablespoons dijon mustard
• 1/2 teaspoon cayenne pepper, using more or less to our taste
• 3 ounces deli ham or prosciutto, torn
• 4 ounces creamy Brie cheese, cubed
• 1/2 cup shredded Swiss or fontina cheese
• 2 tablespoons everything bagel spice ((optional))