In a small pot cook the fruit and sugar over low/medium heat for 5 minutes. The fruit will release moisture and soften. Be sure to stir as this cooks so the sugar doesn’t heat too much in one spot and burn. If you like your jam more smooth than chunky (like I do), use a blender or immersion blender to puree it at this point. Then add the chia seeds and cook another 10 minutes, as it thickens. Remove from heat and stir in the vanilla seeds, cinnamon, or lemon while still hot. Allow to cool before using or storing.