Combine the green and red peppers, sugar, and vinegar in a Dutch oven; bring to a boil. Boil six minutes, stirring frequently. Stir in the pectin and boil 3 minutes, stirring frequently. Remove the pot from the heat and skim off foam with a metal spoon.
Working quickly, pour hot jelly into hot sterilized jars leaving º-inch headspace in each jar. Wipe the jar rims with a clean cloth. Cover the jars at once with metal lids and screw on bands. Process in boiling water bath for 5 minutes.
Makes seven half-pint jars