1. Place corn husks in a large bowl; cover with water. Weight husks down with a can; soak 30 minutes. Drain.
2. Preheat oven to 400°.
3. To prepare filling, pierce potato with a fork; wrap in foil. Bake at 400° for 1 hour or until tender. Peel potato; mash. Heat 2 teaspoons oil in a skillet over medium-high heat. Add 1 cup onion; sauté 4 minutes. Add 1 teaspoon cumin and cinnamon; sauté 30 seconds. Add beans and green chiles; sauté 2 minutes. Remove from heat. Combine potato, bean mixture, cheese, and chopped cilantro.
4. Increase oven temperature to 450°.
5. To prepare masa dough, combine 2 cups broth and corn in a blender; process until smooth.
6. Lightly spoon masa harina into dry measuring cups; level with a knife. Combine masa harina, baking powder, and salt. Add broth mixture and butter to masa mixture; stir until a soft dough forms. Cover.
7. To prepare sauce, heat 2 teaspoons oil in a medium saucepan over medium-high heat. Add 1 cup onion, jalapeño, and garlic; sauté 2 minutes. Add tomatillos and next 5 ingredients (through 1/4 teaspoon salt); bring to a boil. Cover, reduce heat, and simmer 10 minutes. Cool slightly.
8. Place tomatillo mixture and cilantro leaves in a blender. Remove center piece of blender lid (to allow steam to escape); secure blender lid on blender. Place a clean towel over opening in blender lid (to prevent splatters). Blend until smooth.
9. To assemble, working with 1 husk at a time, place 3 tablespoons masa dough in center of husk about 1/2 inch from top, and press dough into a 4 x 3-inch rectangle. Spoon 2 tablespoons bean mixture down 1 side of dough. Fold husk over tamale, being sure to cover the filling with dough; fold over 1 more time. Fold bottom end of husk under. Place the tamale, seam side down, on the rack of a broiler pan lined with a damp towel. Repeat the procedure with remaining husks, dough, and bean mixture. Cover filled tamales with another damp towel. Pour 2 cups hot water in the bottom of a broiler pan; top with prepared rack.
10. Steam at 450° for 1 hour, adding water as necessary to maintain a depth of about 1/2 inch. Let stand 10 minutes. Serve with sauce.