In a blender, combine all ingredients except lemon zest.

Blend for 1-2 minutes on high speed until the mixture is smooth.

Pour mixture into an ice cream maker; add in half the lemon zest and churn for 15-20 minutes until stiff and firm. (If you don't have an ice cream maker, simply pour mixture into a parchment lined pan, and then put that pan into a large sealed tupperware container, then freeze. This will keep the ice cream from crystalizing.)

After the ice cream maker, pour into a parchment lined container or pan. Sprinkle with remaining lemon zest. Serve then or chill to get it a bit more firm.

Store in freezer in airtight tupperware container. When serving, remove from freezer 20 minutes before you eat it, to keep it from being too hard.