Makes 3, 4 oz jars
5 cups of fruit (about 1lb). Can be frozen fruit.
1/2 cup sugar (if you want it less sweet, use a little less)
2 tbsp lemon juice
pinch of salt
Cut fruit into large chunks, but isn't necessary.
In a large pot, combine fruit and sugar. Bring to a boil.
After 10 minutes, use a potato masher to mash up the fruit. Cook for about another 10 minutes, stirring regularly. Dip a metal spoon into the jam, wait about 10 seconds and then run your finger down the middle of the jam. If it leaves a distinct track, it's done.
Turn off heat and transfer jam to clean jars. Seal immediately and let cool to room temperature.
Keeps for about a month in the fridge. The jam can also be frozen.