Cheesy Chicago hot dog croissant-wich | Printable Recipe | Bounded by Buns

Ingredients

• 2 teaspoons vegetable oil
• 1 ⁄ 4 onion, diced
• pinch of salt and pepper
• 1 ⁄ 4 cup cheddar jack cheese, shredded
• 2 tablespoons yellow mustard
• 2 hot dogs, sliced in half
• croissant dough (store bought)
• 1 whole egg
• 1 tablespoon water
• poppy seeds (optional)