Place the eight frozen bean & cheese burritos in a single layer in a 9×13 baking dish. Microwave on high for about 8 minutes, or until the burritos are warmed completely through (check a center burrito to confirm).
While the burritos are microwaving, make the smothering sauce: combine 1 cup fat free sour cream, 7 oz diced green chiles, 2 tablespoons lime juice, 1/2 teaspoon lime zest, 1/4 teaspoon cumin, salt and pepper to taste, and 1/2 cup loosely packed cilantro in a blender. Blend until completely smooth, scraping down the sides as needed.
When the burritos are heated, spread the smothering sauce generously over the top of each burrito in the baking dish. Evenly sprinkle 1 1/2 cups grated Monterey Jack cheese over the sauced burritos.
Set the oven to broil. Place the baking dish under the broiler until the sauce is heated through and the cheese is melted and lightly bubbly—watch closely to prevent burning (about 1–3 minutes, depending on your broiler).
While the burritos are under the broiler, prepare the corn: microwave the 10 oz bag of frozen corn & butter according to the package directions. Transfer the hot corn to a bowl.
To the bowl of corn add 1/2 red bell pepper (finely diced), 3 tablespoons chopped cilantro, salt and pepper to taste, and the juice of 1 lime. Stir to combine and taste-adjust seasoning if needed.
Remove the burritos from the broiler and let them rest for a minute. Serve the smothered burritos hot with the seasoned corn mixture alongside.