This is a take on a classic New England relish recipe, which is quite tasty on crackers, spread on baked Brie, layered in calzone with sausage and Pepper Jack cheese, on burgers, and more.
The traditional (New England) version is sweet and made only with sweet red peppers…
this version uses red, yellow, green, and orange peppers as well as jalapeños and sweet onion and has just a hint of a bite to it.
Needless to say, I like this version best.
INGREDIENTS
•11 cups chopped sweet peppers
•3 cups diced sweet onion
•2 cups sliced jalapeño peppers
•3 cups sugar
•1-1/2 cup cider vinegar
•1-1/2 cup white vinegar
•3 tbsp pickling salt
Note: I cheat and start with thawed frozen mixed pepper slices from Trader Joe’s. If you are using fresh sliced peppers, pour boiling water over the slices in a large bowl and let rest for five minutes before draining and continuing on with the recipe.
Place the thawed frozen peppers – or boiling water soaked and drained fresh peppers – in a large pot with the onion, jalapeño, and remaining ingredients.
Stir until nicely blended, then cook, stirring often, over medium heat until the sugar is dissolved and the mixture comes to a boil.
Reduce the heat and simmer, still stirring often, for 30 or 40 minutes.
Because I am not overly fussed about the size of my pepper and onion pieces at tthe beginning, I give the relish a good whizzz at this point with an immersion blender. If you 
have also been casual about your prep work and do not have an immersion blender, transfer the relish, in batches, to a blender and pulse until chopped but not puréed.
Transfer the relish to prepared canning jars and process in a boiling water bath for ten minutes.
Remove from the water and allow tto cool on a rack. You will hear several “pops” as the jars cool, which means that the seal has taken. Double check this by pressing in the center of each jar lid. If it stays down, the jar is sealed. If it pops up and down (with that popping sound), reprocess that jar for another ten minutes and check the seal again. That should do it.
I generally get between nine and twelve half-pint jars with each batch.