This is found in E1-7: Change of Direction, right underneath the storage device when you start.
Jump on the platform and go across to the giant ball on the right. You want to be more in the corner before you flip gravity. Hit

to make the ball start falling, then

around the time your body would have crossed the first laser. If done correctly, the ball will bounce, throw you off, and come to rest blocking the third laser, allowing you to jump over and get to the microwave. Press

for the achievement.
It takes a bit of practice to get the ball to stop in the proper area, don't get discouraged if you keep hitting the laser or get pummeled into the ground.