Preheat oven to 400 degrees F.

In a medium bowl, combine cornbread mix, milk, and egg.

Stir in corn, cheddar cheese, green onions, and jalapeno (or green chiles).

The mixture will be thick.

Pour the mixture into a greased 8-inch square baking dish.

Bake until a knife inserted in the center comes out clean, about 25 minutes.

Let cool for 15 minutes.

While the cornbread is baking, heat barbecued pork and yellow mustard in a covered saucepan over low heat until hot, about 10 minutes.

Cut cornbread into 6 squares.

Halve the squares horizontally.

Place one half of a square on each serving plate.

Spoon the heated pork mixture on top of the cornbread.

Top with the remaining cornbread half to make a sandwich.