Usage note ... As a collective noun, variety, when preceded by a, is often treated as a plural: A variety of inexpensive goods are sold here. When preceded by the, it is usually treated as a singular: The variety of products is small.
In the American Heritage Dictionary at dictionary.com
n. a large shallow dish; a platter.
(I suspect a lot of Better Homes and Gardens types knew that definition of "charger." But as someone who grew up enjoying many a dinner straight out of the Doritos bag, this was a new one on me when I came across it in a story I was editing and just couldn't figure out how a platter of mashed potatoes could power a cellphone.)