Have never used it but there appears to be different types.
Does anyone have the recipe for the type that you spread on then use a hot knife to smooth?
Yes, but only by weight!
White or milk chocolate:
250ml cream (35% fat content)
750 grams chocolate
250ml cream (35% fat)
500 grams chocolate
Bring the cream to the boil and pour over the chocolate. Stir until all the chocolate is melted. Cover the surface with a piece of cling wrap and allow to set overnight (at least 8 hours). Texture should be like peanut butter, if too hard give it a quick blast in the microwave. Once you have covered your cake leave it to set at room temperature for at least 8 hours.
Yep, just like bonjovebabe said.
I personally prefer to measure by pound. Just remember, 3:1 for white and milk chocolates and 2:1 for dark and semi sweet.
Everything you ever wanted to know about ganache:
(Includes overview, master and other recipes including white chocolate. How to glaze, frost and stack - and more.)
Whipped Chocolate Ganache: