pulse the chips in a food processor until finely chopped
heat heavy cream on stove until simmering (stir to make sure it is all at simmering temp, not just the edges)
pour cream over chips, stir to coat and let sit for a minute to melt
add 1.5 tbs butter to the chip ganache mixture, stir in, let cool for a few minutes
beat frosting butter in stand mixer until light and fluffy
pour in about 1 c of the ganache mixture and beat together
add a pinch salt
add in 4 c of confectioners sugar, more or less until your frosting is the consistancy you need for piping.