Baked Onion Gratin - Better Than Bouillon

Ingredients

• 1/4 cup unsalted butter, divided
• 2 red onions, cut into 1/2-inch wedges
• 2 cooking onions, cut into 1/2-inch wedges
• 1/2 cup heavy cream
• 1 tbsp all-purpose flour
• 2 tbsp Better Than Bouillon Organic Seasoned Vegetable Base
• 1 cup shredded aged Cheddar cheese
• 2 tbsp grated Parmesan cheese
• 2/3 cup bread crumbs