Insert butter to chocolate icing: After chocolate icing reaches gentle ball phase, reduce warmth to simmer and insert remaining cup (2 sticks) butter and remaining teaspoon vanilla. Stir to melt butter, about 2 minutes. Maintain an extremely minimal simmer until finally 1st spherical of cake layers are out of oven. https://sccaps82570.blogminds.com/facts-about-cupcake-lille-revealed-26535250