2 ounces TCHO Dark Baking Discs or 1 TCHO bar, chopped (flavor of your choice)
3/4 cup fine granulated sugar
1 cup unsweetened Dutch-process cocoa powder
2 1/4 cups whole milk
1/3 cup heavy cream
4 large egg yolks
1. Coarsely chop chocolate.
2. In a 2-quart heavy saucepan bring milk, cream, and about half of sugar just to a simmer, stirring until sugar is completely dissolved. Remove from heat and add Dutch-process cocoa powder and chocolate, whisking until mixture is silky smooth.
3. In a bowl with an electric mixer beat yolks and remaining sugar until thick and pale.
4. Add hot chocolate mixture in a slow stream, whisking, and pour into saucepan.
5. Cook custard over moderately low heat, stirring constantly, until a thermometer registers 170°F. (Do not boil.)
6. Pour custard through a sieve into a metal bowl set in ice and cold water and cool.
7. Chill custard, covered, until cold.
8. Freeze custard in an ice-cream maker. Transfer to an airtight container and put in freezer to harden, 1 to 3 hours.
9. Serve now or keep frozen to serve later.