If you're using whole pistachios, shell them and groind them in a mortar. If you're using powder, dry roast it.
Combine half of the heavy cream and half of the sugar together in a bowl and whip for 8-10 minutes till soft peaks form.
Combine the egg and the remaining half of the sugar in another bowl. Mix until the sugar is melted and the mixture thickens.
Combine the pistachio mixture from Step 1 to the egg mixture from Step 3, then add the honey and rum mixing after each addition. Add the cream mixture from Step 2 and mix until smooth. Pour into a mold.
Let it harden in a freezer and it's ready! While it's hardening, mix it many times with a fork and it will come out smooth. Even if you don't mix it, it still should not harden.
If you'd like to give the ice cream a green color, you could add a very small amount of matcha or spinach powder, so as to not affect the flavor.
Adjust the amount of honey and rum to taste 3 g rum is a pretty decent amount. If you don't like rum that much, a few drops would also be fine.
The flavor of the ice cream varies depending on whether you use powder or nuts. It's hard to explain why, but I find the nut version is richer...
Story Behind this Recipe
I love pistachios! I had pistachio ice cream before and I wanted to eat it again~! However, no stores nearby sold it... If you have pistachio paste, you can make it rather easily, but it's expensive... So, after many trials and errors, with some simple ingredients I made it~! This is the recipe that I arrived at.
I really don't like to do dishes so I just gently wiped the mixer I used in Step 2, and used it again in Step 3, and then again in Step 4. As for the color of the ice cream, I used only enough to change the color of the pistachios. The picture on top and in Step 5 is the powder version. The picture in Step 4 uses the nuts. (Overall, even with the pictures, they are still different.)