Ingredients:

  • 2 lbs fresh strawberries, hulled and quartered
  • 1 lb fresh rhubarb, chopped into ½ inch pieces
  • 2 tbsp fresh lemon juice
  • 3 cups granulated sugar
  • 1 packet (4g) powdered fruit pectin
  • ½ tsp unsalted butter

Instructions:

  1. Combine the quartered strawberries, chopped rhubarb, and lemon juice in a large heavy-bottomed stockpot. Stir in the granulated sugar and let the mixture sit for 15–30 minutes to draw out natural juices.
  2. Whisk in the powdered fruit pectin and add the unsalted butter. Set heat to medium-high and bring the mixture to a full rolling boil, stirring constantly for 1–2 minutes.
  3. Continue to simmer the mixture until it reaches 220°F (104°C) on a candy thermometer. Verify the set using the plate test: drop a small amount onto a chilled plate and ensure it wrinkles when pushed.
  4. Ladle the hot jam into sterilized half-pint canning jars, leaving ¼ inch of headspace. Wipe rims clean, secure lids and rings, and process in a boiling water bath for 10 minutes.