A springform pan has a bottom tray with no lip. The sides form a circle and fit into grooves on the bottom pan and spring open and close (or loosen and tighten). If you don't have one, you can use a small 7 inch circular or even square pan with high sides. You won't have the clean edges like you would from a springform, but I suggest doing that before investing in a pan you aren't sure you will use many times in the future.