In a small pot, put the fresh raspberry and water on high heat. Use a fork to mash the raspberry until it becomes smooth, and bring the mixture to a boil.
Reduce the heat to medium and simmer for 10 minutes or less, until the fluids decrease by half; add the lemon juice, powdered erythritol and chia seeds and stir.
Turn off the heat and leave it to cool. After cooling, pour it into a glass jar or container and keep it in the fridge for daily use.
Notes
You can use frozen or fresh raspberry in making this keto jam.
I have a sweet tooth, that is why I have added 2 teaspoons of the powdered erythritol, but you can only add one teaspoon or even don't add any sweaters at all.