Coarsely chop 3/4 of the chocolate, and very finely chop the remaining 1/4.
In a microwave-safe bowl, add the coarsely chopped chocolate only.
With the microwave on full power, beginning with one or two 30 second bursts, begin melting the chocolate, stirring after each burst. Continue melting in 10-15 second bursts until the chocolate is about 70% melted.
Stir the chocolate until it is completely melted and smooth. If this is taking a very long time, give it another 5 second burst in the microwave.
Add half of the finely chopped chocolate to the melted chocolate, and stir vigorously until it is fully melted and smooth. Continue to add chocolate, about 2 tablespoons at a time, and stirring, until you see that the chocolate is starting to take a long time to melt.
Keep stirring the melted chocolate vigorously for about 4-5 minutes. Dip the back of a metal spoon into the chocolate, place it on the counter top and give it 4-5 minutes to set up. If the chocolate sets ups with a smooth, beautiful shine, and no streaks, it is tempered and ready to use.
If the chocolate is not even beginning to set, keep stirring, even adding a little more finely chopped chocolate, and test again. Your chocolate is ready when it sets up hard, shiny, and streak-free in just a few minutes.