I also vote for Mint Chololate Chip! But Vanilla is a close second.
Chazal said, “There is no simchah without ice cream.”
Oh, correct that. Chazal did not say that. Ice cream had not been invented yet. (There are, however, records of it being eaten in Gaonic times.) Had Chazal known about ice cream they would have mandated that it be served every Shabat and Yom Tov.