I have been trying to clean out my freezer to make room for this summer's bounty. The entire bottom drawer was full of peppers... several bags of jalapenos that I vacuum sealed for salsa, and three bags of banana peppers that I must have gotten really cheap at the produce auction. I'd used some of the peppers in a batch of mustard last fall that I really liked, so I decided to make another round to use up the rest of them.
Here is the recipe I use. It was the only mustard recipe I found online that actually used ClearJel as the thickener. Most others called for flour or corn starch, which are not approved for canning. ClearJel (a thickening agent) is NOT the same thing as SureJel (a pecting). It can be purchased online or at Amish-bulk-type stores. I found mine last year at a local bakery, who used it in their pies and agreed to sell me some. Then I found it later on at the Heritage Bake Shoppe at the VA Beach Farmers Market. You want the cook type, NOT the instant kind.
I thawed my peppers in a colander and then ran them through the food processor. It was 2lbs, which translated to a little over 5 cups of chopped peppers.
I am trying to find a good ketchup recipe so that I can give a jar of mustard, sweet pickle relish, and ketchup as end-of-the-year teacher gifts next summer!