First, select the "Preheat" button. Enter the recipe's original time to preheat and press "Start". Once the oven beeps and says, "Preheat Over, Place Food in Oven," place the covered or uncovered casserole in the microwave on the bottom turntable. Select "Convection", then re-enter the casserole's temperature. Enter time, then press "Start". Convection is the recommended mode for casseroles in a convection microwave. If you have two casseroles that have the same approximate cooking time and temperature, you can place one on the high rack and place the other on the turntable. Your cooking time may increase by 5-10 minutes if cooking two casseroles at the same time.