That is the question I asked myself in the dry goods section of my grocery store, surveying the shelf of tapioca products. We're likely best acquainted with tapioca in the form of tapioca pudding, or as the gummy pearls swimming at the bottom of our bubble tea, or as something we stir a spoonful of into pie filling.
But what is it, really, and what does it do?
Tapioca is made from starch of cassava root—a.k.a. yuca. And actually, you can eat yuca on its own, prepared in much the same way you'd prepare any other root vegetable. As Lindsay-Jean writes in this piece, cooked yuca has a sticky texture you'll recognize: Tapioca, its progeny, shares it. It's that stickiness that gives bubble tea and tapioca pudding their distinctive textures.
Tapioca is made by extracting starch from the cassava root: The roots are processed to separate out the plant's naturally occurring cyanide, and what results is the purified starch. You can purchase that starch as is (called tapioca, cassava, or manioc flour or starch—three names for the same thing), or as flakes, sticks, or pearls in a bevy of sizes. The last of these—the tapioca pearls—is so familiar that you, like I, might think of them as being tapioca's truest if not original form.
NB: Some tapioca, sold as "minute" or "instant," generally comes in a granulated form; that's what gives it its "instant" nature. Make sure you're using the kind of tapioca the recipe you're following calls for! Otherwise, your tapioca might not gel up like you're expecting it to.
You can buy flour/starch, instant tapioca, and small pearls at nearly any grocery store. If you want large pearls or boba (large, black, sweetened pearls used for making bubble tea), you may have to order them online or go to a specialty store or Asian grocery. Once you have some on your shelves, it'll stay good in a tightly sealed container for about a year.
And if you're out of tapioca flour/starch, you can grind tapioca pearls very finely and use them in its place. (Flour and pearls are different only in form.)
How do you use tapioca? Tell us about it in the comments.