Are they frozen? Then thaw the frozen biscuits before reheating. If you're using the oven to reheat, loosely wrap the biscuits with foil, then heat at 350° F for 6 to 9 minutes. If you're using the microwave, put the biscuits on a microwave-safe paper towel. Microwave one biscuit on 50% power for 15 to 20 seconds, or until it's warm.