First, remove the one-layered frosting on the sides to gain access to the licorice swirls there. Don't worry if the magic mixer spawns on top of them; they're automatically counted.
Your main priority is the chocolate. By the time you cleared a piece of it, you finished the frosting and the liquorice swirls orders.
You only have 15 moves to do these. Hence, try clearing up the board and destroying the magic mixer as soon as it provides enough frosting for the order. Start-up boosters from several events will really help you in this level.