A muffin was a small, cup-shaped quick bread, often sweetened and made with wheat flour.
Muffins were part of Miles O'Brien's ideal breakfast, along with corned beef, eggs, and oatmeal. (TNG: "The Wounded")
Muffin could also be a term of endearment. Luther Sloan called his wife Jessica muffin. (DS9: "Extreme Measures") It was also Magnus Hansen's nickname for his daughter Annika. (VOY: "Dark Frontier")