This is not the job I like to sign up for (who likes to smell garlic on their hands for 3 days straight?), but this technique looks like too much fun to pass up! Smash, shake, and separate! I’ve also seen this done with two ceramic bowls placed on top of each other (rim to rim) to create a dome for the garlic. The hard surface might work more efficiently than tupperware at breaking apart the garlic.