How to Make It
Preheat oven to 350º. In a large saucepan, heat 2 tablespoons of the olive oil. Cook 1 of the onions over moderate heat until soft and translucent, about 5 to 7 minutes. Add the garlic, jalapeño, chili powder, cumin, crushed red pepper, paprika, oregano, sugar, salt and pepper and cook, stirring, for 1 minute. Stir in the tomatoes and remove from heat. Blend in a food processor or blender until smooth. Return the tomato mixture to heat and simmer for 20 minutes.
In a large skillet over moderately high heat, brown the beef with the remaining onion, 1 teaspoon of salt, and a few turns of pepper, breaking up with a spatula or wooden spoon.
In a large bowl, combine the beef, 1 cup of the sauce, 1 cup of the cheddar and the minced green onions.
Wrap the tortillas in a damp paper towel and warm them in a microwave oven until soft and pliable, about 1 minute.
Spread a thin layer of sauce on the bottom of a 9-by-13-inch glass baking dish. Arrange the tortillas on a work surface. Spoon the beef mixture onto the tortillas and then roll them up and arrange them in the baking dish. Top the enchiladas evenly with the remaining sauce. Sprinkle the tops of the enchiladas with the cheese. Bake for 15 to 20 minutes, until the enchiladas are hot and the cheese is melted.
Serve warm with sour cream, jalapeños and minced green onions.