1/4 cup milk
1/4 cup margarine
1/2 teaspoon onion powder
1/2 teaspoon garlic powder
1/2 teaspoon dry mustard
2 egg yolks
1/2 cup white sugar
1/2 cup packed light brown sugar
3/4 cup margarine
1 cup green bell pepper
1 cup shredded Cheddar cheese
1/2 cup salsa
Preheat oven to 350 degrees F (175 degrees C).
Combine milk, margarine, onion powder, garlic powder, dry mustard, and egg yolks in a medium saucepan and bring to a boil over medium heat. Reduce heat, cover, and simmer for 20 minutes.
In a small bowl, whisk together casserole mix and egg yolks; pour into warm broth and simmer for 5 minutes.
Drain soup and stir in casserole. Stir in Cheddar cheese and salsa; cover, remove from heat, and set aside until cool enough to handle.
Pour soup mixture into shells, placing top layer on a medium baking sheet. Bake in preheated oven for 15 minutes.