Melt 3Tbs of butter in large saucepan and let melt.
Be careful not to burn.
Combine chopped onion, chopped mushrooms, and chopped green chilies in saucepan.
Let marinate on high for about 5 minutes.
Dash veggie mixture with red and black pepper and garlic salt& salt.
Dash the veggies with more seasoning after five minutes.
Make sure to stir well and make sure all veggies cook evenly and are coated with butter.
Adjust temp if needed.
Do not let burn.
After 5 min add 3Tbs half and half and 1Tbs of flour.
Stir for about 1 minute.
Remove from stove and put in bowl.
Melt the remaining 3Tbs of butter in the same saucepan and let melt.
Add fish and cook on high 3 minutes each side.
Dash both sides of fish with red and black pepper, garlic salt, and salt.
Remove from pan.
Chop up the fish into small to med size pieces.
Don't worry if it crumbles.
It doesn't really matter what it looks like.
Throw it back into the saucepan on high for another minute, and then add to veggie mixture.
Add 1cup of cheese and stir mixture until well combined.
Preheat oven to 350F.
Coat bottom of large, deep baking pan with 2 cans of enchilada sauce.
(you can buy disposable pans cheap at grocery stores-usually in bakery aisle) Warm tortilla shells for about 15 sec in microwave, dash with a little water and spoon in about 2Tbs-3Tbs of mixture into shell.
Fold up bottom edge of tortilla and then roll tortilla away from you.
Put in pan.
Repeat until done or tired.
Cover the tops of the enchiladas with the last 2 cans of sauce.