Any-Berry Jam

4 cups crushed blueberries, blackberries, raspberries, or strawberries (hulled). Crush the berries with a potato masher before measuring. If the strawberries are not crushably ripe, slice them first.
1 ½ cups sugar
1 pouch powdered or liquid pectin

Put the berries in a large, heavy pot. Stir together the sugar and pectin in a bowl (if you are using liquid pectin, skip this step), then stir the sugar and pectin thoroughly into the berry mixture. Bring the berries to a boil over medium-high heat, stirring constantly. You are looking for a full, rolling boil--the kind that can't be stirred down. Boil for one minute, then ladle the jam into very clean jars (leave an inch of headroom for expansion in the freezer), cap, cool to room temperature, and then use or freeze.

(It needs to be frozen as it has much less sugar than what you need to store at room temperature.)

Makes 4-5 cups

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