Sour cream is a dairy product rich in fats obtained by fermenting a regular cream by certain kinds of lactic acid bacteria. The bacterial culture, which is introduced either deliberately or naturally, sours and thickens the cream. Its name stems from the production of lactic acid by bacterial fermentation, which is called souring. The taste of sour cream is only mildly sour.

Sour cream, made out of cream, contains from 18 to 20 percent butterfat–about 14 grams per 4 fluid ounce serving–and gets its characteristic tang from the lactic acid created by the bacteria. Commercially produced sour cream often contains additional thickening agents such as gelatin, rennet, guar and carrageen, as well as acids to artificially sour the product.

Light, or reduced-fat, sour cream contains about 40 percent less butterfat than regular sour cream because it is made from a mixture of milk and cream rather than just cream. Fat-free "sour cream" contains no cream at all, and is made primarily from non-fat milk, modified cornstarch, thickeners and flavoring agents.

Martha Stewart (née Kostyra; August 3, 1941) is an American business magnate, author, magazine publisher, and television personality. As founder of Martha Stewart Living Omnimedia, she has gained success through a variety of business ventures, encompassing publishing, broadcasting, merchandising, and electronic commerce. She has written numerous bestselling books, is the publisher of the Martha Stewart Living magazine, and her syndicated talk show, Martha, is broadcast throughout the world.

In 2004, Stewart was entangled in the ImClone insider trading affair and there was speculation that the incident would effectively be the end of her media empire. She began a comeback campaign in 2005 and her company returned to profitability in 2006. Stewart rejoined the board of directors of Martha Stewart Living Omnimedia in 2011 and became chairman of her namesake company again in 2012.

Martha Stewart was born in Jersey City, New Jersey to middle-class Polish American parents, Edward "Eddie" Kostyra (c. 1912 – 1979) and Jadwiga Martha Ruszkowski Kostyra (b. September 16, 1914, Buffalo, New York – d. November 16, 2007, Norwalk, Connecticut). She lived in Jersey City until the age of 3, when her family moved to Nutley. She was raised in Nutley along with her five siblings. She took the name "Grace" for her confirmation name before graduating from Nutley High School.