Blue Cheese Stuffed Burgers | Reynolds Brands

Ingredients

• 1 tablespoon olive oil
• 1/2 teaspoon salt
• 1 teaspoon ground black pepper, divided
• 4 cups sliced mushrooms
• 1 red onion, thinly sliced
• 1 pound ground beef
• 1 tablespoon Worcestershire sauce
• 1/4 cup crumbled blue cheese
• 4 hamburger buns, split
• Lettuce leaves and/or sliced tomatoes (optional)