In a large mixing bowl add egg yolks and sugar. Using a whisk, beat until pale yellow in color and the mixture forms soft ribbons. Set a side.

Pour milk into a large saucepan.

Split the vanilla bean in half lengthwise and drop it into the milk. Heat on medium, bringing to a slow simmer, stirring often. Do not boil.

Once hot, slowly pour while stirring, a little of the hot milk into the egg mixture. When combined slowly pour in the rest. This tempers the eggs (bringing them up in temperature slowly) so they don't cook or scramble.

Pour this mixture back into the sauce pan and heat on low until thickened slightly. About 2 to 5 minutes. Test by running a finger down the spatula, when the line doesn't fill back in, you're good to go. Again, do not boil.

When the gelato base has thickened, pour through a fine mesh sieve into a clean bowl. This will catch any egg impurities. Scrape the bottom of the sieve.

Lastly, measure and add in the vanilla extract.

Allow the gelato base to cool completely before refrigerating over night.

Once the vanilla bean gelato base has chilled completely, following the manufacturers instructions, pour the ice cream base into the ice cream maker and churn until thick.

Transfer the thickened ice cream into a freezer-safe container and freeze for 4 hours or overnight.

Serve scoops in ice cream cones or into bowls and pour hot espresso over top.