Add raspberries and water to a saucepan over medium heat.
Stir frequently as berries warm; they'll soften and begin to release juice.
Smash raspberries with the back of a rubber spatula; continue stirring until mixture reduces and becomes jammy (about 8–10 minutes); color deepens and liquid thickens.
Transfer to a bowl and let cool slightly (about 5 minutes).
Once cooled, stir in chia seeds; let sit 2 minutes so seeds begin absorbing liquid.
Gently whisk Greek yogurt into the raspberry-chia mixture.
Taste and add sweetener if needed (raspberries vary in tartness).
Transfer to a container with a lid or to individual cups covered with plastic wrap.
Chill in the fridge for at least 4 hours or overnight.
Serve as-is or layer with extra Greek yogurt on top.
Top with fresh raspberries for a bright berry burst. (optional)
Video
Notes
This low carb raspberry chia pudding tastes best when made ahead; overnight chilling allows flavors to meld and chia seeds to fully hydrate for creamy texture.
Stir pudding once after 2 hours of chilling, then again before serving; this prevents settling and keeps texture even throughout.
Store in an airtight container for up to 5 days; make a batch Sunday night for grab-and-go breakfasts all week.