It has a large inedible leaf. The stalk is what you are after. The stalks can get sizable, and grow in a patch. I transplanted a root ball in smaller clumps and got more rhubarb. Easy to grow in good soil and not to much shade. Doesn’t need a huge amount of water, but dry growing conditions will create smaller more bitter stalks.

Most times I see rhubarb in food it has been cooked to a mash consistency and sweetened. For things like pies, jams, sweet sauces for Ice cream and the like in my experience. I’m sure there are other uses. It’s pretty sour raw IME.

Easy to store long term in the freezer as well. Cut and remove leaf, wash, either dice or leave whole, package then freeze.