I highly recommend using couverture chocolate if you can get it because that's the best type of chocolate for tempering. It is also the highest quality chocolate that does not contain unnecessary additional ingredients. It tastes amazing! I used these dark chocolate and white chocolate today. They are one of my favorites. But! If you cannot get couverture chocolate, just use any chocolate you get. I believe in starting with what you can get. It's not going to be exactly the same result but it's still amazing and delicious because it's chocolate!!