Heat water in a pot, add sweetener and pinch of salt and allow to dissolve. Add raspberries, crushing them with a potato masher. Boil for 5 to 8 Minutes.
Use a strainer to strain the raspberries, then place them in a square or rectangular oven-safe dish with a lid. Freeze for 2 Hours.
Use a knife to cut into cubes; then place in the Ace Nova blender. Press Frozen Desserts, using the measuring cup/tamper handle to help the blender fully process all the cubes. Press the same setting again, for a smoother texture.
Serve immediately or, if you want a firmer texture, empty into an oven-safe dish and freeze for 2 more Hours. Enjoy!