Makes about 4 half-pint/500 ml jars
THIS IS A VIBRANT, SWEET-TART JAM CELEBRATING THE AMBROSIAL COMBINATION of rhubarb and raspberries, and is a great way to use up the uncontrollable, fleeting bounty of rhubarb that takes over the Midwest in that hopeful window between April and June. As it’s also low-sugar, this jam is best refrigerated or frozen for longer storage, and isn’t suitable for canning.
1 pound/453 g rhubarb stalks, cut into ½-inch/1.25 cm pieces (about 4 cups)
6 ounces/170 g fresh raspberries
1¾ cups/350 g granulated sugar
1 tablespoon freshly squeezed lemon juice
¼ teaspoon ground cinnamon
⅛ teaspoon fine sea salt
½ teaspoon pure vanilla extract
Combine all the ingredients except the vanilla in a large, nonreactive bowl. Mix thoroughly and cover. Refrigerate for at least 6 hours, or overnight.
Pour the fruit mixture into a 4- to 5-quart/3.75 to 4.75 L, heavy-bottomed pot. Set the pot over medium heat and bring the mixture to a boil, stirring often. Let boil for 10 to 12 minutes, or until thickened. Remove the pot from the heat and stir in the vanilla. Let cool before ladling into jars or using in recipes. Store in the refrigerator for up to 3 weeks, or freeze for up to 1 year.