Ice cream
From Memory Alpha, the free Star Trek reference.
Ice cream is an ancient Human dessert. It is made from dairy products, such as milk, custard, or cream.
The chef made homemade ice cream for dessert aboard Enterprise in 2154. (ENT: "Fortunate Son")
The food synthesizers aboard the USS Enterprise offered numerous selections on tape of ice cream flavors, including vanilla, strawberry, cherry, peach, chocolate, chocolate wobble, coconut, rocky road and pistachio. (TOS: "And the Children Shall Lead")
Wesley Crusher told Jono in 2367 that his favorite ice cream dish was the banana split, which was available in Ten Forward aboard the USS Enterprise-D at that time. Jono's unfamiliarity with the operation of a spoon, however, soon led to the dessert being splattered across Wesley. (TNG: "Suddenly Human")
Deanna Troi was extremely fond of chocolate ice cream. In 2366, she dreamed of a real chocolate sundae with real chocolate ice cream and whipped cream. (TNG: "The Price") In 2368, she enjoyed a chocolate sundae with chocolate ice cream, chocolate chips, chocolate fudge and a cherry in Ten Forward. (TNG: "The Game") In 2376, she visited Reginald Barclay and asked for only one scoop of chocolate ice-cream, because she was watching her figure. However, Barclay's cat Neelix ate from the ice cream. (VOY: "Pathfinder") She also got some chocolate ice cream on Jupiter Station from Dr. Lewis Zimmerman's holographic friend, Haley, even though she said she hardly deserved it. (VOY: "Life Line")
In 2374, Ch'Targh taunted Alexander Rozhenko in the Rotarran's mess hall, asking him if he would like a glass of root beer with a lump of ice cream. (DS9: "Sons and Daughters")
Later that year, Chakotay introduced ice cream to the former Ramuran tracer Kellin, who remarked that she could eat it all day. (VOY: "Unforgettable")
Captain Janeway used to enjoy coffee ice cream every now and then. (VOY: "Persistence of Vision")
