Cinco de Mayo Tacos

Name: Cinco de Mayo Tacos
Ingredients: 1 box hard-shell corn tortillas; 2 Teaspoons ancho chili powder; 1/4 Teaspoon ground cumin; 1/8 Teaspoon dried oregano, preferably Mexican oregano; 1/8 Teaspoon garlic powder; 1/8 Teaspoon onion powder; 1/8 Teaspoon paprika; Pinch of cayenne; 1/2 Teaspoon kosher salt; 1 Pound ground beef, preferably grass-fed; 1/2 Cup frozen corn kernels, thawed; Grated Monterey Jack, for serving; Tomatillo or tomato salsa, for serving; 1 ripe avocado, pitted, skinned, and sliced thinly; Sour cream, for serving