Onions
From Soyjak Wiki, The Free Soycyclopedia
An Onion is a vegetable, Farmers and gardeners can grow onions from seeds or from bulbs. If they plant seeds, they must later pull out most of the young plants so the rest can grow better. This is called 'thinning.' A different way to plant onions is to plant young bulbs. This is faster, but the onions that grow this way are weaker than the onions that started as seeds.
Association with soyjaks
Onions are heavily associated with Soyjaks due to 4chan filter that automatically turns the word "Soy" into onions, if you spot someone typing onions on 4chan chances are they are relatively new to Soyjaks in general, but this isn't always necessarily the case.