- 1 lb blackberries (4 cups)
- 3/4 cup sugar
- 2 tablespoons powdered fruit pectin
- 1 tablespoon fresh lemon juice
- Mash blackberries with a potato masher or a fork in a large bowl.
- Stir together berries, sugar, pectin, and lemon juice in a 12-inch nonstick skillet, then boil, stirring occasionally, until slightly thickened, about 7 minutes. Transfer jam to a large shallow bowl and chill, its surface covered with wax paper, until softly set, at least 30 minutes. (Jam will set further if chilled longer.)