Coat a 9- or 10-inch quiche dish with nonstick cooking spray. Spread bread cubes evenly in the quiche dish. Set aside.
Crumble turkey sausage into a medium skillet; cook until brown. Drain off fat. Pat with paper toweling to remove excess fat. Sprinkle cooked sausage over bread cubes in quiche dish.
In a medium mixing bowl beat together eggs, milk, and sour cream. Stir in Monterey Jack and cheddar cheeses. Pour egg mixture over sausage in quiche dish. Cover and refrigerate for at least 2 hours.
Uncover and bake in a 325 degree F. oven for 35 to 40 minutes or until center is set and top is golden brown. Remove from oven. Let stand for 5 to 10 minutes before cutting. To serve, cut strata into wedges. Spoon some salsa on top of each serving. Makes 6 servings.
Assemble strata. Cover and refrigerate up to 24 hours before baking as directed above.