Have you ever slaved over candies or chocolate dipped something only to have it dry with a chalky looking coating over it? This is called blooming and happens when the chocolate is exposed to a wide range of temperatures. It's OK to eat, but it doesn't look very pretty. So how do we make professional looking candies and chocolate dipped treats at home? The answer is tempering.
Officially, tempering chocolate is a lengthy process in which you melt the chocolate to a temperature of 115 degrees (for dark chocolate), then cool it to 84 degrees, then warm it again until it reaches about 90 degrees and keep it there. It's tricky and takes some practice but we've streamlined the process to make it a lot easier and all you need is a bowl and a pot.

The right ratio
Here's how you do it. Start with at least 1 pound of finely chopped dark chocolate. Place two-thirds of the chocolate in a large bowl set over a pot with about 2 inches of barely simmering water in it.

melting
Warm the chocolate, stirring constantly, until just melted. Remove the bowl from the heat.

cooling
Add the remaining chocolate to the bowl and stir until completely melted.

Dip. Cookies, dried fruit, fresh fruit, pretzels, even potato chips.

Feel like a pro.
Pour any unused tempered chocolate onto a parchment-lined sheet. Let cool, then break up in to chunks and use for your next batch of tempering (or just chop and toss into cookie batter).

From: traci | 3/19/10 at 1:08 pm
I think that tempering chocolate in the microwave is just as easy. The key is to chop the chocolate, heat in 30 second intervals and stir, stir, stir. I know it's not the "official" way, but it's much less fussy than getting out the thermometer and double boiler, in my opinion...