Prepare yourself for science boffin speech:
Tempering chocolate controls the crystals in chocolate so that only small crystals are produced. Tempering is when you melt the chocolate, so that it is smooth and snaps when broken. If a recipe requires tempered chocolate, then unfortunately, temper you must.
On with the tempering:
There are four main ways to temper chocolate and I will here quote Miss Hope from ‘Miss Hope’s Chocolate Box’ or the chocolate bible.
TEMPERING FOR RICH PEOPLE – Buy a tempering machine and use.
TEMPERING FOR SMARTY PANTS PEOPLE – A bit of a faff, but we’ll go with it.
Melt the chocolate in a bowl over a pan of warm water. Pour around three-quarters of the melted chocolate onto a marble slab. Work it across the slab until it has reached exactly 28°C. Using a palette knife, scrape the chocolate back into the bowl and heat until it reaches 31-32°C for dark chocolate, 30-31°C for milk chocolate, or 27-28°C for white chocolate.
TEMPERING FOR PEOPLE WITH A SOCIAL LIFE – Chop the chocolate and put about two thirds into a bowl. Heat 5cm water in a pan and pop the bowl on top of the pan, making sure that the bottom of the bowl is not touching the water. Allow the chocolate to melt slowly. Once liquid, turn off the heat, remove the bowl and wrap the base in a tea towel to keep it warm (slightly odd, I know). Add the rest of the chocolate and stir until the chocolate is the correct temperature (see TEMPERING FOR SMARTY PANTS PEOPLE)
TEMPERING FOR PEOPLE WITH JOBS, CHILDREN, PETS, FRIENDS OR A TRAIN TO CATCH – Pop the chopped-up chocolate into a microwaveable bowl and melt at 400-600W, checking it every 30 seconds and stirring. When the chocolate looks nearly melted, but there are still a few bits bobbing on tops. Take out of the microwave and stir the chocolate until smooth. It should have thickened slightly.
I have to say that I mostly use a microwave, but the other methods are worth a go, and do produce glorious chocolate. Alternatively, you can do the third method, but not measure the temperature. See what works for you.