Peach and/or nectarine jam is one of my favorites. I like to add a little bit of ginger or vanilla to the mix, but honestly, I often leave it plain. The 60:40 fruit to sugar ratio works for me. I rarely peel the peaches in advance and instead just pass the pulp through a food mill to remove the skins after they have softened. The only potential pitfall of peach or nectarine jam is that it can sometimes be too sweet if the fruit is very ripe. When that’s the case, I add a splash of sherry vinegar just before jarring.