Whisk together the egg yolks and half of the sugar in a medium sized bowl.

Combine the other half of the sugar with the milk and cream in a heavy bottomed sauce pan and heat until just below a simmer. Whisk in the instant coffee until it is dissolved.

Take about a cup of the hot cream/milk mixture and whisk it into the bowl with the eggs to temper them. Whisk the egg/milk mixture back into the pot with the cream and cook over a low heat until thickened. You are making custard. Do not let it boil or you will have scrambled eggs in your cream!

When thick (about 5 minutes), remove from the heat pour though a fine mesh strainer into a bowl set over ice water. This stops the cooking process and helps the custard cool quickly. Whisk in the vanilla once cool. Chill in the refrigerator until very cold.

Freeze according to your ice cream maker's instructions and at the end mix in 1 tsp of finely ground coffee.