El Sombrero Inc. is a 1952 Mountain View built diner with a 1961 Kullman dining room. It had been known as the Avon Grove Diner. By the 1990s, it had been mansard-ed, and since then, the stainless steel and the mansard roof have been covered with irregularly sized boards, painted in a vibrant red, white and yellow to harmonize more with its current usage as a tortilleria and carniceria. The overall lines of the exterior of the diner show through despite these modifications, and the stainless shows through a bit where some of the renovations have dropped off.