1-Heat raspberries, granulated sugar, water, and lemon: Heat raspberries, granulated sugar, water, and lemon juice over medium high heat in a medium sized saucepan until boiling.
2-Reduce the heat to medium: Reduce the heat to medium. Cook, stirring often, until the fruit has thickened. To test that the jam is thick enough, place a plate in the refrigerator until chilled. Place a small dollop of jam on the chilled plate. If the jam stiffens, it’s fully cooked. If liquid runs from the jam, it needs to continue cooking.
3-Transfer jam to a small bowl, and: Transfer jam to a small bowl, and refrigerate for 1 hour until fully cooled.