1 c. milk
2 tbsp. flour
2 tbsp. butter
1/4 c. grated Parmesan cheese
1 tsp. Dijon mustard
Salt & pepper to taste

Melt butter; blend in flour. Add milk slowly to avoid lumps. Add remaining ingredients. Cook over medium heat until thickened. Great over seafood or pasta. Variation: Add 1 tablespoon sherry.