English Cottage Pie

INGREDIENTS

• 1 tablespoon all-purpose flour
• 1 tablespoon butter, softened
• Cooking spray
• 1 1/2 cups chopped onion
• 1/2 cup chopped carrot
• 1 (8-ounce) package cremini or button mushrooms, thinly sliced
• 1 pound extra-lean ground beef
• 2 tablespoons no-salt-added tomato paste
• 1 cup fat-free, lower-sodium beef broth
• 1/4 teaspoon freshly ground black pepper
• 1/4 cup chopped fresh parsley
• 1 tablespoon fresh thyme leaves
• 1/2 teaspoon salt
• 3 cups leftover mashed potatoes
• 3/4 cup (3 ounces) shredded reduced-fat sharp white cheddar cheese, divided
• Paprika (optional)