Place the beans in a saucepan and mash with a potato masher. Add the cooked rice, spices, and water. Heat 5 to 10 minutes. Meanwhile, prepare the vegetables. Heat the tortillas quickly (just to soften) in a preheated skillet, toaster oven, or microwave. Place a line of bean mixture down the middle of each tortilla. Top with lettuce, scallions, tomato, and salsa. Tuck in the top and bottom edges, roll into a burrito, and serve immediately, topped with additional salsa if desired.