12 corn tortillas, softened
12 ounces grated mild cheddar cheese
cup minced onion
Ancho Chile Sauce (prepare ahead, recipe follows)
Using about of the cheese, place a small amount just off-center in each tortilla, sprinkle on some of the onion, and roll up. Place enchiladas in a shallow baking pan. Ladle sauce over enchiladas, sprinkle with remaining cheese (and additional onion, if you'd like), and back at 350 degrees until cheese melts and the sauce bubbles.
Ancho Chile Sauce
4 ancho chiles (dried poblanos)
2 T. oil
2 oz. ground beef
2 T. flour
1 tsp. ground cumin
c. tomato sauce
4 cloves garlic
1 tsp. dried oregano
1 tsp. salt.
Using kitchen tongs to turn them, toast chiles on a griddle or skillet over medium heat until just fragrant (20 to 30 seconds each side). Rinse chiles under cold water, remove stems and most of the seeds and veins, chop coarsely, and place in blender. Fill blender with very hot water and soak chiles for 20 minutes.
Discard soaking water. Add 1 cup of fresh water to chiles and blend mixture until smooth. Add another 3 cups water and blend again. Pour mixture through a strainer into a bowl, pressing lightly. Set aside.
Heat oil in a saucepan over medium heat, add ground beef, and cook until browned, stirring constantly. Add flour and continue cooking and stirring for about 2 minutes. Add cumin, then stir in about cup of the pureed chiles, allowing to thicken, then add the rest of the puree. Add tomato sauce, bring to a boil, reduce heat, and simmer.
While the sauce is simmering, grind garlic and oregano to a paste in a spice grinder or molcajete. Add the paste to the sauce, stir in salt, and simmer uncovered for about 20 minutes. Remove from heat and use in a recipe.