Because induction cookers use electromagnetic energy to generate heat, they work only with cookware made of iron or magnetic gauges of steel. (If a magnet sticks to its base, your pan will work on an induction stove.) For nonmagnetic cookware, the answer might be an induction interface disk, a Ping-Pong paddle–shaped device that sits under your incompatible pot and acts as a converter, transferring heat by conduction. We tested three models priced from $48.95 to $99.95, using them to boil water and make pancakes under non-induction-ready pans. One small carbon steel disk never managed to bring the 2 quarts of water to a boil or fully cook a pancake, and its metal feet scratched our cooktop’s glossy surface. We had more success with the other two models, made of smooth 18/10 stainless steel. These models reliably boiled water and cooked pancakes—albeit in twice the time it would take using straight induction and a compatible pan (or about the same time it would take on a gas burner). We strongly favored the Max Burton Induction Interface Disk, which has an aluminum core for speedy heat distribution and a comfortable, heatproof rubber handle. At $48.95, it costs less than a new induction-ready saucepan.