Carlson's Donuts in Severn, Maryland has garnered such a loyal following that customers can hardly fathom getting their donut fix anywhere else. Known especially for their potato flour donuts, the owners also have a second location where they sell donuts—in a Thai restaurant. Sounds odd? Maybe, but even if you're full on pad thai, you don't want to pass up the sweet, light and fluffy concoctions on your way out. Regardless of which location you choose, you'll want to bring cash payment and arrive early enough before the donuts sell out (and sell out they do).