Char's Breakfast Casserole - Lettuce Entertain You

Ingredients

• 12 slices multigrain bread
• 2-3 Tbsp butter (room temperature)
• ½ cup butter
• ½ lb mushrooms, sliced
• 2 cup onion, thinly sliced
• 1 ½ lbs chicken Italian sausage
• ¾ lb cheddar cheese, grated
• 6 eggs
• 2 ½ cup milk
• 3 tsp Dijon mustard
• 1 tsp dry mustard
• ½ tsp nutmeg
• 2 Tbsp parsley, chopped