makes 3 1/2 pints
3 cups (12 ounces) chopped rhubarb
3 cups (12.75 ounces) frozen wild blueberries
3/4 cup (6 ounces) sugar
2 teaspoon no-sugar pectin (like Ball’s)
Add the rhubarb to the bowl of your food processor. Pulse until finely chopped. Transfer to a glass microwave-safe bowl. Add blueberries and stir in sugar. Microwave on HIGH for 8 minutes, until boiling. Stir in the powdered pectin. Microwave on high for 5 more minutes, until thickened and bubbly.
Transfer to a container, let cool and refrigerate for up to three weeks or process in clean, sterilized jars using a hot water bath.