This is the recipe I use for hot pepper relish -- it is sweet and hot, just a touch of flavor from the cider vinegar, and really good on burgers.
Last year I used a mix of jalapeno and poblano chile; this year it's just poblano (blight got the jalapeno plant!), with a couple of stray bell peppers tossed in. Don't worry about them being green or red, either; use what you have.
Hot Pepper Relish
18 red chili peppers, seeded and stemmed
18 green chili peppers, seeded and stemmed (can use bell pepper for less heat)
6-8 onions peeled (4 pounds)
1 tablespoon canning or regular salt
2 1/2 cups cider vinegar
2 1/2 cups sugar
Put peppers and onions through food chopper, or chop in water in blender and drain. Place in 6 qt. kettle. Add salt; cover with boiling water. Let stand 10 minutes.
Drain and discard liquid. Add vinegar and sugar to vegetables. Bring to boil, simmer 20 minutes. Ladle into jars.
Process in boiling water bath 15 minutes.
This makes about seven pints.