Whisk 3/4 C sugar with 8 egg yolks.
Scald 1 3/4 C half-and-half with 1 split vanilla bean. When hot, not boiling, whisk slowly into eggs. Put mixture on top of a double boiler and stir to thicken. Custard should coat back of a spoon. Lower heat and add 2 T butter. Turn off heat and add 2 more T butter. Add 1 1/2 C cream, mix and strain. Chill and churn in ice-cream maker.