Instructions
Day one: Select full-size, nearly green, firm cantaloupes. Wash, halve, seed, peel, and cut into 1-inch cubes; weigh 5 pounds into a large glass bowl.
Tie red pepper flakes, cinnamon, cloves, and ginger in a spice bag. Boil 5% cider vinegar and water, turn off heat, add spice bag, and steep 5 minutes.
Pour hot vinegar mixture and spice bag over melon. Cover and refrigerate about 18 hours.
Day two: Drain liquid into a large saucepan and boil. Add both sugars and dissolve. Add melon, return to a boil, then simmer until translucent, about 1 to 1 1/4 hours. Remove melon; boil liquid 5 minutes, return melon, and bring to a boil.
Pack melon into hot pints, initially leaving 1-inch space, then cover with syrup to 1/2-inch headspace. Remove bubbles, adjust, wipe rims, and apply lids. Process 15/20/25 minutes for 0–1,000/1,001–6,000/above 6,000 ft.