You have to make 60 striped candies in 50 moves, and it is hard because you have all candy colors present on the board. In addition, you usually need at least 2 moves to make a striped candy and burst it. But the mystery candies that you have make it much easier.
You really need to make a colour bomb and combine it with a striped candy (more than once) to complete this level. Try to make sure there are as many candies as possible on the board of the same colour as the striped candy before you combine it with the colour bomb. Each of these will count as a striped candy for your ingredients collected.