grease 13 x 9 glass baking dish. in 10-inch skillet over medium heat, cook pork-sausage meat, stirring frequently to break up sausage, until thoroughly cooked and no longer pink. use slotted spoon, remove sausage to paper towels to drain. cut french bread into 1/2inch cubes. drain and chop mushrooms. in baking dish, combine sausage, bread cubes and mushrooms. in large bowl, whisk together eggs, milk, italian seasoning, garlic powder, and pepper. pour egg mixture over sausage mixture. cover with plastic wrap and refrigerate overnight. preheat oven to 350. bake strata, uncovered, 1 hour. remove from oven and sprinkle evenly with mozzarella and cheddar cheeses. bake 15 minutes longer.