Makes 1 quart
- 1 large pasilla negro chile, stemmed, seeded, deveined
- 1 1/3 cups half-and-half
- 2 ounces Mexican chocolate, chopped into small pieces
- 3 ounces semi-sweet chocolate, chopped into ¼-inch pieces
- 4 egg yolks
- ½ cup sugar
- 1 1/3 cups heavy (whipping) cream
- 1 ½ teaspoons pure vanilla, preferably Mexican
- ¼ cup Negra Modelo beer
- In a small skillet heated over medium, toast the chile, pressing it flat against the skillet with a metal spatula until it is very aromatic—about 10 seconds per side. Place in a small saucepan, add the half-and-half, Mexican chocolate and the semi-sweet chocolate, and heat over medium until steaming (but not boiling). Remove from heat. Cover and let steep for 10 minutes, then pour into a blender jar and process until the chile is completely pureed.
- Set up a 4-quart saucepan, filled halfway with water, into which you can nestle a 3-quart stainless steel bowl. Bring the pot of water to a boil over high heat while you’re preparing the custard base. Reduce the temperature under the pot of boiling water to maintain a gentle simmer.
- In the 3-quart stainless steel bowl, whisk together the egg yolks and sugar until thoroughly combined, then whisk in the chile-infused chocolate mixture. Set the bowl of custard base over the simmering water and whisk frequently, scraping down the sides of the bowl regularly with a rubber spatula, until the mixture thickens noticeably, about 5 minutes. The custard is sufficiently cooked when it reaches 180 degrees on an instant-read thermometer. (You can also test it by dipping a wooden spoon into the custard, then running your finger through the custard: if the line holds clearly, the custard has thickened sufficiently.) For the finest texture, strain the mixture through a fine sieve into a clean bowl.
- Fill a large bowl halfway with ice. Nestle the bowl of strained custard in the ice bath. Whisk the mixture until it is completely cool. Refrigerate if not using immediately.
- Stir the heavy cream, vanilla and Negra Modelo into the base. Freeze in an ice cream freezer according to the manufacturer’s directions. Scrape into a freezer container and freeze for several hours to firm.