- 1/2 vanilla bean
- 11 oz Mexican chocolate (3 1/2 disks; preferably Ibarra), coarsely chopped
- 3 3/4 cups half-and-half
- 3 large eggs
- Scant 1/4 teaspoon salt
- Special equipment: an instant-read thermometer; an ice cream maker
- Halve vanilla bean lengthwise and scrape seeds into a 3-quart heavy saucepan. Add chocolate and half-and-half and bring to a boil over moderate heat, whisking. Remove from heat.
- Lightly beat eggs with salt in a bowl, then add hot chocolate mixture in a slow stream, whisking. Transfer custard to cleaned saucepan and cook over moderately low heat, stirring constantly with a wooden spoon, until custard registers 175°F on thermometer, 1 to 5 minutes. Immediately pour through a fine-mesh sieve into a metal bowl. Put bowl in a larger bowl of ice and cold water and cool, stirring occasionally.
- Freeze custard in ice cream maker. Transfer ice cream to an airtight container and freeze until hardened, about 1 hour.