Roughly chop chocolate with a sharp knife and place in a arge bowl.
Heat heavy whipping cream in a microwave for 1-2 minutes, or until hot. (Alternatively, you can heat the cream on stovetop until almost boiling, but not quite to a boil.)
Pour hot cream over chopped chocolate and let it sit for good 2-3 minutes.
Add salt and whisk the mixture gently from the center, stirring in one direction and slowly incorporating cream into the chocolate, until it's nice and smooth, about 2 minutes. (NOTE: As you stir the mixture, it’ll go through a few stages. At some point, it’ll look questionable, and you may wonder if you had messed up somehow. But don’t you worry; it’ll come together in just a little bit. Keep stirring gently until the mixture is glossy smooth and flawless.)
TIP: If ganache is smooth for the most part, but you notice some solid chocolate in it (especially if you’re using chocolate chips), you may need to heat it up gently. Here’re 2 ways to go about it: 1. Microwave it in 30-second increments at 50% power, stirring each time, until all the chocolate is melted. 2. Or place the bowl with ganache over double boiler and gently heat the ganache until all the chocolate is melted.
To add some shine, you may stir in butter, if desired.
When ganache is warm, it's quite runny, which is perfect for glazing or drizzling. Ganache thickens as it cools, if you want more frosting-like texture. You can also reheat it in a microwave in 15-second increments at 50% power to make it runny again.