Savory Onion Tarte Tatin with Balsamic Honey Glaze - Quickie Treats

Ingredients

• 1 tablespoon salted butter
• 1 large yellow onion, cut in half lengthwise
• 1 tablespoon honey
• 1 tablespoon balsamic vinegar glaze
• 1 teaspoon kosher salt
• 1 teaspoon black pepper
• 1 sheet puff pastry, thawed
• 1 large egg
• 1 tablespoon water
• 1 teaspoon white sesame seeds
• 2 scallions, sliced
• 1 teaspoon crushed red pepper flakes