Temper the chocolate: Set up your double boiler and be sure the water doesn’t touch the bottom of the bowl. Bring a double boiler to a low simmer over medium-low heat, and reduce heat as needed to avoid boiling and steam. (Steam and water can cause chocolate to seize.)

Add two thirds of the chopped chocolate, and stir continuously until the chocolate is uniformly liquid.

Using oven mitts, remove the bowl from the pot and wipe away any condensation on the bowl with a towel. Continue to stir slowly, and a little bit at a time add the remaining chocolate, melting completely before adding more. Continue to stir slowly until the temperature reaches 82F for dark chocolate, or 79F for white or milk chocolate. (if your environment is warmer than 75F, have a bowl of ice or an ice pack on hand to move the chocolate on and off of. Do not leave the chocolate on the ice too long, or it will start to set.)

Return the bowl to the simmering double boiler, and stir until the chocolate is heated to 88-91F for dark chocolate, or 85-87F for white or milk chocolate.

Then, remove the bowl from the heat for the second and final time, and wipe away any condensation. Wrap with the towel to keep warm, and move back onto the pot if the chocolate gets too cold.

Test the temper by dipping a knife into the chocolate. If it dries glossy and even within 3 minutes, you have achieved temper, and your chocolate is ready to be used. If it dries dull and streaky, try again by heating and cooling once more (repeating steps 3 and 4.)