A Rich Onion Pot Roast for Sunday Dinner and the Best Leftover Sandwiches This Steakhouse Onion Pot Roast is a tender chuck roast cooked low and slow with lots of onions, A1 sauce, Worcestershire, pepperoncini, butter and savory onion seasoning. The onions practically melt into the cooking liquid and create a rich gravy that tastes somewhere between classic pot roast, French onion soup and an old-school steakhouse dinner. Serve it with mashed potatoes and vegetables for Sunday dinner, then save the leftover beef and gravy for some really fantastic sandwiches later in the week. Before You Jump to the Recipe…