Prickly Pear Jelly

From the garden

• 3 lb ripe prickly pear fruits (tunas), spines singed off, peeled — deep magenta fruit gives the classic jewel color; to yield 2 1/2 cups juice

From the pantry

• 3½ cups granulated sugar — measured out in advance
• 1¾ oz powdered fruit pectin — one standard box
• ¼ cup bottled lemon juice — a safety ingredient, not a flavoring — prickly pear juice is low-acid and needs it for water-bath canning; never reduce it

1. Handle every fruit with thick leather gloves and tongs — beyond the visible spines, the skin carries glochids, hair-fine barbs that bury themselves in bare skin. Holding each tuna with tongs, rotate it over a gas flame or grill until the glochids singe away with little flares, then scrub under running water.
2. Trim both ends of each fruit, slit the skin lengthwise, and peel it back off the flesh. Chop the flesh, put it in a heavy pot with 1/2 cup water, and simmer 10 minutes, mashing as it softens. The seeds are stone-hard — mash around them, don't fight them.
3. Strain through a dampened jelly bag or several layers of cheesecloth without squeezing. Fill a boiling-water canner and bring it to a simmer; keep 4 half-pint jars hot in the water and prepare the lids.
4. Measure exactly 2 1/2 cups of juice into a tall pot and stir in the lemon juice and pectin. Bring to a full rolling boil over high heat, stirring constantly, then add all the sugar at once, return to a rolling boil that stirring can't knock down, and boil hard exactly 1 minute. Off the heat, skim the foam.
5. Ladle into the hot jars leaving 1/4 inch of headspace, wipe the rims, and screw the lids on fingertip-tight. Process in boiling water covering the jars by 1–2 inches for 10 minutes. Altitude adjustment: add 5 minutes at 1,001–6,000 feet, 10 minutes above 6,000 feet.
6. Rest 5 minutes, lift the jars onto a towel, and cool undisturbed 12–24 hours before checking the seals. The color alone earns it a spot on the gift shelf.