Place garlic cloves in a medium bowl, first cutting the large cloves in half. Mix in the red bell pepper.
In a large saucepan over medium high heat, place the vinegar and white sugar. Place ground dry mustard and celery seed in the liquid mixture. Add salt and peppercorns. Bring to a boil. Boil 5 minutes. Stir in garlic and peppers. Continue boiling 5 minutes. Remove from heat.
Place garlic and peppers in sterile container to within 1 inch of the top. Fill with remaining liquid to within 1/4 inch from the top. Seal and store in the refrigerator approximately three weeks before serving.
If you blanch the garlic you won't have to wait the whole three weeks.