Great company dish!
Preheat oven to 350.
Split fillets lengthwise and roll up, fastening with a toothpick if necessary.
Place in shallow 10x16" baking dish.
Pour milk over fish.
Add salt and pepper; bake 30 minutes.
When done, pour off milk and add slowly to melted margarine into which the flour has been added.
Add cheese and stir until melted.
Add lemon juice and pour sauce over fillets.
Brown quickly under broiler.
Serves 3-4, depending on the size of the fillets.
