A baked potato was a meal consisting of a specially prepared potato. Preparation initially involved baking a potato, slitting it open, and adding various complimentary ingredients. A twice-baked potato involved the removal of the baked insides, mashing it, and placing the mixture back into the potato shell and baking it again.
On Thursday, 19 August 2152, Enterprise NX-01's Chef was planning on serving twice-baked potatoes with roast duck and raspberry sauce, asparagus, and ginger. But when he fell ill, Hoshi Sato replaced him and served her family oden recipe. (ENT: "Singularity")
During the imprisonment of Tom Paris and Harry Kim in an Akritirian prison in 2373, the first thing Paris wanted to eat following their escape was a steak dinner. Upon their return, Paris asked Kim what they should have as a side with their steak dinner, mentioning a baked potato, big mound of deep-fried onion rings and grilled mushrooms as optional sides. (VOY: "The Chute")
In 2374, following the apparent cancellation of Worf and Jadzia Dax's wedding, and the subsequent end of the fasting associated with the Kal'Hyah, Julian Bashir ordered a steak with mushrooms, along with a baked potato with sour cream and chives from Quark's, after he had not eaten in days. Unfortunately, he was prevented from enjoying his meal by the fact that the wedding was back on, and the ritual was not yet completed. (DS9: "You Are Cordially Invited")