1(14-ounce) can chopped tomatoes, drained, with ⅓ cup juice reserved
2(15.5 ounce) cans white, black, or kidney beans (or a mixture of any two), drained and rinsed
Kosher salt and freshly ground black pepper, to taste
1(15-ounce) can sweet corn kernels, drained
3cupsroughly chopped spinach
4medium sized (8-inch) flour tortillas
2cups(8 ounces) shredded Monterey Jack or cheddar cheese
Chopped fresh cilantro for garnish (optional)
Sour cream to serve (optional)
Salsa to serve (optional)
Instructions
Preheat the oven to 400°F. Spray a 9-inch round cake or baking pan with nonstick cooking spray.
Heat the oil in a large skillet over medium heat. Add the onion, cumin, chili powder, and garlic and sauté until you can smell the spices and the onion is softened, about 3 minutes. Stir in the tomato paste, tomatoes with the reserved juice, and the beans. Season with salt and pepper and simmer until everything is well blended and hot, about 3 minutes. Add the corn and spinach and stir until spinach has wilted and everything is well blended and hot, about 3 minutes. Add salt and pepper as needed.
Place one tortilla in the prepared pan. Spread one fourth of the bean and vegetable mixture evenly over the tortilla, then sprinkle ½ cup of the shredded cheese evenly over the top. Repeat with three more layers, ending with the last quarter of the bean mixture, and then the last ½ cup shredded cheese.
Bake the tortilla casserole until hot throughout and the top is lightly browned and the cheese has melted, 20 minutes. Let sit for 5 minutes, then cut into wedges using a sharp knife and serve with a spatula or better yet a pie server. Sprinkle with cilantro, if desired, and serve with salsa and sour cream on the side if you like.
Notes
You can make this a day ahead of time, cover it with plastic wrap or aluminum foil and put it in the fridge overnight; just take it out and let it sit at room temperature for about 20 minutes while the oven preheats to 400 degrees. Bake uncovered.