R. Crumb's Keep on Muffin'

R. Crumb's Keep on Muffin' is a muffin store that opened on the same block as Edna Krabappel's muffin store, Edna's Edibles, along with 'Muff Said, H.R. Muffin Stuff and Muff Mart.

Behind the Laughter
It is named after Robert Crumb, an American artist and illustrator who goes by that pen name. The figure on the sign is modeled after the figures in the Keep on Truckin' one-page comic.