Preheat the oven to 400°F. Lightly coat a 9-by-13-inch baking dish with nonstick cooking spray.
If you have not already done so, slice the hot dogs into rounds and brown them in a large skillet. Set aside.
In a large mixing bowl, whisk together the whole milk, eggs, hot sauce, and yellow mustard.
Add both boxes of corn muffin mix and stir until combined.
Stir in the diced green chiles and corn, if using. Season the batter with black pepper and garlic powder to taste.
Fold in the browned hot dogs and about half of the shredded cheddar cheese.
Pour the mixture into the prepared baking dish and spread it into an even layer.
If using chili, spoon it over the top in dollops. Use the back of the spoon to lightly swirl it across the surface without fully mixing it into the batter.
Sprinkle the remaining cheddar cheese evenly over the top.
Bake uncovered for about 30 minutes, until the center is set and the casserole is golden around the edges.
Turn on the broiler and broil just until the cheese is browned in spots. Watch it constantly so the top does not burn.
Let the casserole rest for a few minutes, then scoop or cut into portions and serve.
