Lots of El Salvadorans live in the Mission, and here they find the pupusa, a stuffed cornmeal round that is more or less the hamburger of their homeland. It usually comes filled with beans, cheese, or meat -- sometimes in combination -- and is eaten along with seasoned shredded cabbage. The kitchen at this plain-Jane, home-cooking place also makes the more unusual rice-flour pupusa, as well as other dishes popular in Central America, including fried plantains, tamales filled with pork and potatoes, and chicharrones (fried pork skins) and yucca.