Mustard Sauce for Baked Ham

2/3 C sugar
1 T dry mustard
4 eggs
1/4 C vinegar
1 T butter

Mix dry ingredients first. Beat four eggs until lemon colored and fluffy. Gradually add dry ingredients and vinegar. Microwave on high for one minute. Stir well. Continue to microwave at one-minute intervals (I often use a lower power), stirring each time until mixture thickens but is still creamy. You will need to watch it carefully so that it does not overcook. Do not allow it to bubble. When it overcooks, it loses its creamy texture. Stir in butter and cool. Refrigerate until serving. Serve with baked ham. Store any leftovers in the fridge. This is also delicious spread on ham or sausage sandwiches.