I pick these up frozen at a near by Asian store and fry them.  Very simple!
Recipe: At Freedoms Table Cookbook

1. -1 LB. Ground Beef

2.- 1/2 Cup Chopped Onion

3.- ¼ Cup Thinly Sliced Green Onions

4.- 2 Tbs. Grated Carrots

5.- 1/8 Tsp. Sesame Oil

6.- 1 Egg

7.- 1 Package Wonton Wrappers (round)

8.- Vegetable Oil

In a large bowl combine cooked ground beef, onions, carrot, and egg mix well.

Place tablespoon of the meat mixture on half of each wonton wrapper; use your fingers to wet the outer edge of each wonton; fold over and seal by pressing the edges together. In a large skillet heat 11?s inches of oil to temperature of 300F to 325F and fry until brown. Remove the fried yaki mandu to a paper- lined plate to drain.