When melting chocolate, remember that you are not heating or cooking it. Chocolate will melt in the heat of your hand, and that is how gentle the melting process should be. Chocolate that is grainy, or turns thick and seizes up in a solid mass, has been overheated.
It is also important that the chocolate be kept dry, as even one drop of water will cause it to seize. When you are melting chocolate in a bowl over simmering water, take the pan off the heat before putting the bowl on top then reduce the heat so that the water simmers gently and does not boil, as boiling water creates droplets of steam that may fall on the chocolate. Do not add any cold liquids to the chocolate until it has melted.
When you are melting chocolate in a microwave, use the Defrost setting and check its progress every 30-60 seconds; the chocolate will retain its shape even though it has softened.
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