Key Lime & Vanilla Bean Buttermilk Ice Cream

1. Mix sugars together in a small bowl. Set aside.
2. Split vanilla bean lengthwise, scrape seeds out with small knife and place in a saucepan. Throw in the pod as well (we’ll take it out later).
3. Add heavy cream and 1/3 of sugar to the saucepan with the vanilla and heat over low heat until sugar is dissolved and cream is steaming. Remove from heat, cover and allow to steep for 15-30 minutes.
4. Meanwhile, in a bowl, beat the egg yolks and 1/3 of the sugar until sugar is dissolved.
5. While you wait for the vanilla to steep in the cream, mix remaining sugar with juice and zest of lime in a small saucepan and heat over medium. Allow to cook until slightly thickened, set aside.
6. Uncover the cream, remove the bean pod and slowly drizzle into egg yolks while whisking continuously.
7. Return to the saucepan, add lime/sugar mix, and heat over low heat. Stir constantly with a spatula from the bottom and sides until it coats the back of the spatula. (A good test is to run your finger down the spatula and if the lines run together, it’s not done yet—they should remain separated.) Remove from heat.
8. Stir in buttermilk and chill immediately over an ice bath until completely cooled.
9. Place in the refrigerator overnight.
10. Follow your ice cream machine manufacturer’s instructions for freezing.

Makes about 2 quarts.