Here's what you need:
7 Baby Seedless Cucumbers, peeled and chopped
2 Egg Whites
1 small lime (1.5 TBSP juice, lime zest)
1 packet of true lemon
1 TSP Midori Melon Liquor
1/2 cup water
1/2 cup sugar
Vanilla to taste
Chile Powder to taste
1 - Supersaturate water and sugar on the stove, then add vanilla to taste and reduce heat and let cool.
2 - Puree Cucumbers, True Lemon, Lime Juice, Lime Zest, and Midori.
3- Beat Egg Whites until you get them pretty frothy, then add the puree to the bowl and mix well.
4 - Add mix to the solution once cool
5 - Cover it up and throw it in the fridge overnight.
6 - When you're ready, add your stuff to the ice cream maker and let it do its thing.
7 - When its done, dust it with chili powder to taste, and add thin slices of lemon and lime for garnish. It melts pretty fast, but it'll stay frozen long enough to be good.
Why it works: I sat down and tried to figure it out for a while. To be honest I have no idea. The Midori brings out the cucumber flavor, and the alcohol in it prevents the formation of ice crystals, giving it a less abrasive texture. The egg whites make it creamier, and the extra citrus helps the flavor and accentuates the chili bite. The spice will creep up on you, and its not overbearing. Finished product is a nice green color, and its very refreshing on a hot day. Past that I've got nothin'...
Disclaimer: This may or may not have been a total fluke. I might have had a good experience by accident, so I hope it works as well for you as it did for me. Let me know how it turns out.