Vegetarian Burritos

1 tablespoon vegetable oil
1 onion, chopped
4 cloves garlic, minced
1 can kidney beans, drained
1 can black beans, drained
1 cup water
1 can petite diced tomatoes
1 cup fresh spinach, chopped
1/2 c. sliced mushrooms
3 tablespoons chili powder
2 teaspoons ground cumin
4 teaspoons prepared mustard
1 pinch cayenne pepper, or to taste
3 tablespoons soy sauce
4 cups cooked and mashed sweet potatoes
12 (10 inch) whole or multi-grain tortillas, warmed
8 ounces shredded Cheddar cheese, reduced fat

Directions
1.Preheat oven to 350F.
2.Heat oil in a medium skillet, and saute onion, mushroom and garlic until soft. Stir in beans, and mash well.  Add tomatoes. Gradually stir in water, and heat until warm. Remove from heat, and stir in the chili powder, cumin, mustard, cayenne pepper and soy sauce.
3.Divide bean mixture and mashed sweet potatoes evenly between the warm flour tortillas and top with chopped spinach. Fold up tortillas burrito style, top with cheese, and place on a baking sheet.
4.Bake for 12-15 minutes in the preheated oven, and serve.