Milkshakes were an Earth beverage
Eugene Jones favoured banana milkshakes. He ordered one when he visited Happy Cook. Gary forced him to drink the milkshake whilst Josh performed the Heimlich Maneuver upon him, in an attempt to recover a Dogon Sixth Eye he had swallowed. (TW: Random Shoes)
The Doctor bet he could get Martha Jones the greatest chocolate milkshake she ever had. They travelled to such places as Costa del Centauri VI and 1950s Wisconsin, until they finally went to Korova Moo. (IDW: Agent Provocateur)