Monitoring the microwave cooking time is crucial to prevent overcooking, or you can get a rubbery cake texture. After 60 seconds of cooking, check the cake's doneness by inserting a toothpick into the center. If the toothpick comes out clean, your cake is ready. If not, continue cooking for another 30 seconds, then recheck. Adjust the cooking time as needed to ensure your cake is perfectly cooked without becoming overdone.