Chicken Linguine

Ingredients

• 1 lb. sliced fresh mushrooms
• 1/2 c. dry sherry
• 2 Tbsp. reduced-calorie margarine, melted and divided
• 4 (4 oz.) skinned, boned chicken breast halves
• 1/2 c. chopped onion
• 1/4 c. plus 2 Tbsp. all-purpose flour
• 3 c. canned no-salt added chicken broth, undiluted and divided
• 1 (8 oz.) carton nonfat sour cream alternative
• 1 (16 oz.) pkg. linguine (uncooked)
• 1/2 c. (2 oz.) shredded reduced-fat Monterey Jack cheese
• 1/4 c. plus 2 Tbsp. freshly grated Parmesan cheese, divided
• 1/8 tsp. freshly ground black pepper
• 1/4 c. fine, dry breadcrumbs