(adapted from this recipe on Ice Cream Ireland)
1 cup sugar
4 egg yolks
1 1/4 cups cream
1 cups milk
1 tsp vanilla extract
2 Tbsp Bailey’s Irish Cream Liqueur
Beat the sugar and egg yolks together until thick and pale yellow.
Bring the milk to a simmer. Remove from the heat. Beat the milk into the eggs and sugar in a slow stream. Pour the mixture back into pan and place over low heat. Stir until the custard thickens (around 140 degrees Fahrenheit).
Allow the custard to cool.
Mix in the cream and the liqueur, beating for one minute. Freeze using a ice cream machine.