Our Chocolate Bowls make a handsome presentation for gelato.
Prepare an ice bath, and set aside. In a large saucepan, bring the milk, cream, and cocoa to a simmer over medium-low heat. Combine the egg yolks and sugar in the bowl of an electric mixer fitted with the whisk attachment, and beat on medium speed until pale yellow and very thick, 3 to 5 minutes.
Add half the milk mixture to the yolk mixture, and whisk until blended. Stir combined mixture back into remaining milk mixture. Add the chocolate, and cook over low heat, stirring constantly, until mixture is thick enough to coat the back of a spoon.
Pass the mixture through a very fine sieve into a large mixing bowl. Set the bowl in the ice bath, and chill completely. Freeze in an ice-cream maker, according to manufacturer's instructions, until gelato just holds its shape. Transfer to a metal loaf pan, cover with plastic wrap, and freeze until firm, at least 2 hours.
Use the best-quality chocolate you can find.