SOAK tamale wrappers in warm water 30 minutes. Heat oil in large skillet over medium heat. Sauté onion in oil. Add diced green chiles, chili powder and taco sauce. Remove from heat. Stir in shredded chicken. Set aside.
BRING chicken broth to boiling in small saucepan. Beat shortening in large bowl with electric mixer until light and fluffy. Gradually add cornmeal mix until combined. Gradually add chicken broth until cornmeal mix is thicker than for cornbread, but still moist.
DRAIN wrappers. Place 3 tablespoons cornmeal mixture in center of each wrapper or overlapped corn husks; spread to 4 x 2 inches. Top with 2 tablespoons chicken mixture in center. Fold over short ends; fold over sides until tight against the cornmeal. Tie bakers string around each end and in center.
Tamales may be frozen in freezer bags or used immediately.
PLACE tamales in vegetable steamer. Cover with corn husks, if desired. Place tamales in steamer so that long ends are resting on sides of pot.
STEAM 1 hour if tamales are refrigerated. Heat an additional 15 minutes if tamales are frozen. To test for doneness, tamales will be firm and set, and will begin to pull away from the wrapping.
SERVE topped with any of the following: chili, salsa, guacamole, sour cream or shredded Monterey Jack cheese.