Just take two bowls, put the big one in hot water, then put the chocolate in the small bowl, then put the small bowl in the big bowl and stir it slowly.

Steam in a steamer. Put the chocolate pieces in a plate, put them in a steamer, and steam them in hot water until the chocolate melts. It should not be too long to heat the chocolate in a steamer to avoid too much water vapor in the plate. Use a microwave oven for heating. Put the chocolate block in a microwave oven container and heat it on high fire until the chocolate melts. If there is no microwave oven, you can use an oven instead.