Steps
1. Preheat the oven to 350°F (180°C).
2. Slice the croissant in half lengthwise without cutting all the way through.
3. Spread mustard on one side of the croissant.
4. Layer baked meat, baked onion slices, and Bejing cabbage on top.
5. Drizzle BBQ sauce over the filling.
6. Close the croissant and wrap it in foil.
7. Bake in the preheated oven for 10-15 minutes until heated through.
8. Serve warm and enjoy!