Combine first 3 ingredients in a Dutch oven. Add water to cover; bring to a boil. Cover, reduce heat, and simmer 2 1/2 hours or until meat is tender. Drain meat, reserving broth; set broth aside. Shred meat with a fork; set aside.
Cover dried cornhusks with hot water; let stand several hours or until softened. Drain well. If husks are too narrow overlap 2 husks to make a wide one. If too wide, tear off one side.
Remove and discard seeds from chiles; place in a saucepan, and cover with water. Bring to a boil; reduce heat and simmer 20-25 minutes or until chiles are tender. Drain chiles, reserving 3/4 cup water; place softened chiles in container of blender. Add reserved water and blend 1 minute or until smooth; set aside.
Melt 2 teaspoons shortening in a small saucepan; add flour and cumin, stirring until smooth. Cook 1 minute stirring constantly. remove from heat, and stir in 1/2 cup chile mixture and 3/4 teaspoon salt; add to shredded meat, stirring well. Set aside.
Bring reserved beef broth to a boil. Combine corn masa, 1 teaspoon salt, and 1/2 cup plus 1 tablespoon shortening in a large bowl. Stir in 1 cup plus 2 to 3 tablespoons hot beef broth to make a stiff dough. Add the remaining chile mixture to the dough, mixing well.
Place 2 1/2 to 3 tablespoons masa dough (depending on husk size) in the center of each husk, spreading to within 1/2 inch of the edge. Place 2 tablespoons meat mixture in center. Fold short ends of husks to center, enclosing filling; roll up from unfolded side. Tie with string or strip of softened corn husk.
Place a cup in center of a steaming rack or metal colander inside of a large pot. Add enough water to fill pot below rack level and keep tamales above water. Stand tamales on flded ends around the cup. Bring water to a boil. Cover and steam 1 hour or until tamale dough pulls away from corn husk; add more water as necessary. Serve with Picante sauce, if desired.
Note: Steamed tamales can be frozen. Allow to cool; place in plastic bag, or wrap them securely in aluminum foil, and place in freezer. To reheat, follow steaming procedure until tamales are thouroughly heated.