This stage relies less on the exact launching angle. Just time your launch so that it does not destroy the laser shooter prematurely. Launch into the top left portion of the center square. You can either touch the side or slide through the top.
Power Activation Point
Activate your power so that you can push some blocks towards the center and some to the right. Your goal is to bring a few metal balls to the right, so that they can reflect the lasers being shot.
First Shot Result
The center square gets disturbed, resulting in the death of the three pigs in the center. The lasers bounce off the metal circles you pushed, killing the other three pigs floating in the bubble. Then lastly, the laser shooter bump into the left over metal and killing itself.
You are finally rewarded with the three star mastery for your trouble.