Add the raspberries and water to a small saucepan over medium heat.
Cook for 5–7 minutes, stirring occasionally, until the raspberries soften and begin to break down. Use a spoon or fork to mash the raspberries to your desired consistency.
Stir in the monk fruit sweetener, chia seeds, lemon juice, and vanilla extract.
Reduce the heat to low and simmer for 2–3 minutes, stirring constantly, until everything is well combined.
Remove from heat and let the jam sit for 10–15 minutes to thicken as the chia seeds absorb liquid.
Transfer to a jar or airtight container and let cool completely before sealing.