Add the frozen raspberries to a small pot on warm on low heat, stirring often, until the raspberries defrost and release their liquids. Mash with a fork until all the berries are broken up. Remove from heat. Stir in the chia seeds (and maple syrup if using) and set aside for 10 to 15 minutes to thicken. Done!
Once cooled, put this raspberry chia jam in a mason jar and refrigerate for up to 5 days.
I like to smear this on toast, add a scoop to warm oatmeal or overnight oats, or even as the middle layer between tiered cakes!