Caramelized Onion Baked Mac and Cheese | Scratch Pantry

Ingredients

• 1 ⁄ 4 cup oil
• 4 large yellow onions, thinly sliced
• 1 ⁄ 2 teaspoon salt
• 1 tablespoon balsamic vinegar
• 2 teaspoons brown sugar
• 1 pound dried pasta
• 1 ⁄ 2 cup butter
• 1 ⁄ 2 cup all-purpose flour
• 2 cups half and half
• 4 cups milk
• 1 teaspoon salt
• 1 teaspoon pepper
• 4 cups sharp cheddar cheese
• 2 cups Gruyere Cheese