Heat oven to 350° F. Coat a 13 x 9 x 2-inch baking dish with nonstick cooking spray.
Heat oil in a large nonstick skillet over medium-high heat. Add onion and garlic and cook 3 minutes, stirring occasionally. Stir in beans, tomato sauce, chili powder and cumin; simmer 3 minutes, stirring occasionally.
Gradually stir in spinach until wilted, about 3 minutes. Stir in cilantro and lightly mash bean mixture with a potato masher. Spoon about 3/4 cup of the bean mixture down center of each tortilla and tightly roll up; place seam-side down in prepared dish.
Sprinkle cheese over enchiladas; cover and bake at 350° F for 30 minutes. Serve warm with tossed salad, if desired.
A great source of lean protein and fiber, beans are also good for your budget.