Cut the onions into 1/2-inch slices. In a large sauté pan on high heat, add some oil and then the onions. Break up the onions and coat them with the oil. Continue on high heat until the water from the onions has released and evaporated. As soon as the pan is fairly dry, turn down the heat to low. Stir the onions so all pieces get equal time making direct contact with the pan: if onion pieces are on top of each other they will not brown. Some people cheat by adding sugar, but there’s plenty of sugar in the onions to give you a really nice caramelized color and flavor.