In a mixing bowl, beat the heavy whipping cream, vanilla, and powdered sweetener until thickened.
In a small bowl, whisk the gelatin and the cold water until combined. Add to the mixer and beat until stiff peaks form.
Scoop 1 tablespoon-sized mounds of whipped cream onto a pan or tray. Freeze for 15-20 minutes.
Melt the chocolate chips and coconut oil in the microwave or using a double boiler until smooth.
Remove ice cream mounds from the freezer and coat each with melted chocolate or drizzle over the ice cream and swirl with a knife to create a marble effect.
Optionally, sprinkle with sugar-free sprinkles. Freeze for another 10-15 minutes until firm.