Wash cauliflower flowerets and boil in salt water (4 tsp. canning salt per gallon of water) for 3 minutes. Drain and cool. Combine vinegar, sugar, onion, diced red pepper, and spices in large saucepan. Bring to a boil and simmer 5 minutes. Distribute onion and diced pepper among jars. Fill jars with cauliflower pieces and pickling solution, leaving 1/2 inch headspace. Adjust lids and process half-pint or pint jars for 10 minutes. About 9 half-pints.
USDA Complete Guide to Home Canning