1 c cream
6 to 12 oz semisweet chocolate, chopped (or chips) (amount will depend on use)*
Bring cream to a simmer and pour over chopped chocolate. Stir until smooth. Flavor as desired. Refrigerate until firm. Can be remelted and used as a sauce.
*The more chocolate used the firmer the ganache will be. 6 oz will still firm in the fridge but will be soft at room temperature. 12 oz will hold be very hard in the fridge and still hold it's shape at room temperature (so if you will be using it as a piped frosting this is a good consistency)