2 lbs. elbow macaroni, cooked
2 qts. milk
3/4 c. butter
1 c. flour
1 tbsp. salt
1 1/2 tsp. dry mustard
2 lbs. sharp Cheddar cheese, grated
1/4 c. minced onion
2 tsp. Worcestershire sauce
25 tomato slices, 1/4 inch thick
3 lbs. wieners, halved lengthwise

Heat milk in double boiler. In large kettle, melt butter; stir in flour, salt, mustard; cook, stirring often, 10 minutes. Stir in hot milk; cook stirring, until thickened. Add cheese, onion, Worcestershire. Stir gently until cheese is melted. Remove from heat and stir in macaroni.