Make-Ahead Christmas Morning Strata

Ingredients

• 6 bacon slices, diced
• 4 breakfast sausages, casings removed and meat crumbled
• 1 onion, finely chopped
• 1 pint cherry tomatoes
• 4 cups spinach
• 8 eggs
• 3 cups milk
• 2 tsp Dijon mustard
• 1 tsp salt
• ¼ tsp freshly ground pepper
• 1 cup shredded old Cheddar cheese
• ½ Italian bread loaf, sliced into 2-inch cubes, about 4 cups (200g)
• Butter, for pan