A four-ingredient slow-cooker butter beef recipe combines cubed beef stew meat, butter, and a packet of dry onion soup mix for a hands-off meal that can cook while you are away. The recipe calls for three pounds of beef stew meat, half a cup of butter, and one 1-ounce envelope of dry onion soup mix, and it serves eight.
Preparation takes about five minutes. The beef and butter go into the slow cooker, the onion soup mix is sprinkled on top, and the lid goes on.
The meat cooks until tender—eight hours on Low or four to five hours on High—with a stir once or twice during cooking.
The recipe suggests serving the beef hot over cooked egg noodles. 
According to the provided nutrition facts, each serving contains 437 calories, 35 grams of fat, 2 grams of carbohydrates, and 28 grams of protein. The recipe does not specify a brand of onion soup mix or a particular cut of stew meat beyond cubed beef stew meat, and it does not include instructions for thickening the cooking liquid or adjusting seasoning. 
Editorial Notes