When broiling, leave the oven partially open.
The most probable reason that people believe they should broil with the oven door open is that many ovens have an internal thermostat that temporarily shuts off the broiler element if the temperature climbs too high. Keeping the oven door open, therefore, maintains a lower temperature in the oven, keeps the broiler element on, and allows the food to brown without overcooking. Not all ovens have this feature, so check your manual.
Bottom line? Follow the manufacturer’s instructions for the use of your broiler for safe operation. Our recipes account for differences among home broilers by giving a time range and visual cues for doneness.