Make brownies in a spring form pan (use a mix or your own recipe).
Poke little holes in the brownie and drizzle flavoring (liqueur) on top, just enough to moisten brownies.
In a double boilter, melt semi-sweet chocolate with 1 cup of liqueur, stirring until well blended.
Set aside (off the stove), and let the liquid cool a little, almost to lukewarm, but warm enough to melt butter into.
Make sure the cream and butter are NOT cold, but room temperature.
Grate 3/4 cup of sweet butter into chocolate mixture, stirring the entire time.
Whisk in 3/4 cup of heavy cream.
Pour chocolate mixture onto brownie bottom.
Chill till hard, best to leave in fridge overnight.