Blueberry Jam by Epressurecooker

blueberries, granulated sugar, lemon, lemon extract, butter, cinnamon

– 1 pound (450 grams) blueberries (fresh or frozen)
– 1 /2 to 1 lb. (225 to 450 grams) granulated sugar
– 1 washed lemon
– 1/4 teaspoon lemon extract
– 1 tbs. butter (optional, vegans can omit)
– pinch of cinnamon (optional)