Roast beef may be reheated using the microwave oven or by slipping slices of it in hot gravy. It's a good idea to store leftover roast beef as a chunk and not sliced, and it should also be tightly wrapped before putting it into the refrigerator. Leftover gravy should also be stored in the refrigerator, as it will be useful when reheating the leftover roast beef.
Roast beef can be reheated in several ways. The following are two ways of going about the process.
Microwave the leftover gravy on High until it is very hot. Set aside.
Carve the roast beef into thin slices, and then divide the slices into two servings.
Place one of the servings into the microwave and set it on Low. Heat the serving in 30-second intervals until it is warm, but not too hot. Repeat with the other serving.
Pour the hot gravy over the sliced roast beef and serve.
The following shows how to reheat the roast beef on a stove using the leftover gravy.
Put the gravy on a pan and heat it on the stove.
While the gravy is cooking, carve the roast beef into thin slices.
Once the gravy is boiling hot, place the slices in the gravy until they are warmed through. Serve.