1 (14 1/2) ounce can whole tomatoes, drained
2 tablespoons corn or canola oil
2 cups coarsely chopped onions
3 cloves garlic, finely chopped
6 canned whole green chiles (two 31/2 ounce cans), drained, seeded and coarsely chopped
2 fresh or canned jalapeno chiles, drained if canned, seeded and finely chopped
10 corn tortillas, about 6 inches in diameter
1 cup shredded sharp cheddar cheese
1 cup shredded jack cheese
1/2 cup pitted black olives, halved
1 cup sour cream for serving (optional)
Salt and freshly ground black pepper
Position a rack in the middle of the oven. Preheat the oven to 375. Have ready a baking dish with at least a 6-cup capacity. A rustic-looking ceramic baking dish makes a good choice. Chop tomatoes coarsely, and set aside. In a large skillet, heat 1 tablespoon of the oil over medium heat for 1 minute. Add the onions and cook until they soften, about 5 minutes, stirring often.
Stir in the garlic and continue cooking for another minute. Return the heat to medium-low and add the green and jalapeno chiles. Add the tomatoes and any of the juices that have accumulated on the plate, using a fork to break the tomatoes up into pieces. Continue cooking for 5 minutes, stirring constantly.
Tear seven of the tortillas into about eight pieces each and add them to the pan. Cook for another minute, stirring to coat the tortilla pieces with the sauce. Remove the pan from the heat. Add salt and pepper to taste. Spoon about 1/3 of the tortilla mixture into the baking dish, spreading it evenly. Sprinkle about 1/3 of the cheddar and 1/3 of the jack cheese over it. Spoon all the olives evenly over the cheese. Repeat the tortilla and cheese layering twice, ending with the cheese layer. Brush the 3 remaining tortillas with the remaining 1 tablespoon oil. Use scissors to cut each tortilla into eight wedges.
Arrange the tortilla wedges in two overlapping circular rows to cover the cheese completely. Sprinkle the top generously with black pepper. Bake until the filling is bubbling gently and the tortilla topping is lightly browned, especially on the edges, about 25 minutes. Serve immediately, with sour cream if desired. Makes 6 servings.