Remove mushroom stems and finely chop. Heat pancetta in large skillet
on medium heat. Cook 2 minutes or until crispy. Add mushroom stems,
onions, and garlic. Cook 5 minutes or until tender, stirring occasionally.
Stir in 1 1/4 cups of RAGU® Tomato, Garlic & Onion Sauce, 1/4 cup cheese,
and 1/2 cup breadcrumbs. Cook 4 minutes or until mixture has thickened,
stirring occasionally.
Arrange mushroom caps on foil-lined baking sheet. Spoon filling into
mushrooms.
Combine remaining cheese and breadcrumbs; sprinkle on top of mushrooms.