Coat a 10-inch cast-iron or other ovenproof skillet with nonstick spray. Heat pan over medium-high heat. Add turkey to pan; cook until done, about 5 minutes, stirring to crumble. Stir in salsa; cook until liquid evaporates, about 1 minute. Remove turkey mixture from pan.
Add water, tomato sauce, cumin, and salt to pan; bring to a boil. Stir in noodles; cover, reduce heat to medium-low, and cook, stirring frequently, until noodles are tender and liquid is absorbed, about 12 minutes. Top noodle mixture with turkey mixture and black beans; cover and cook until heated through, about 2 minutes.
Preheat broiler to high. Uncover pan. Sprinkle evenly with cheese and top with tomato and scallions. Broil until cheese melts, about 2 minutes.
Serving size: about 1 cum