Place strawberries into a food processor and blend until roughly pureed. You can also chop by roughly by hand.
Place chopped strawberries in a small saucepan over medium heat. Using a wooden spoon, mash and stir frequently until strawberries come to more of a liquid consistency (about 7-10 minutes).
Add the lemon juice and liquid sweetener if using. Stir to combine.
Remove the saucepan from heat and stir in the chia seeds. For the first 5 minutes, stir frequently with a fork to avoid clumping. Allow the jam to completely cool before placing in an air-tight container.
Store in the fridge.