We have outposts of SEA-based Top Pot Doughnuts here in DFW now. They're quite good but not great. Glazed Donut Works in Deep Ellum is a better local choice.

For greatness though, I'd go with Blue Star Donuts (PDX). Their blueberry bourbon basil donut is incredible but everything I sampled from there is really good.

Also amazing is Spalding's Bakery (LEX). They make excellent old-school throwback donuts. Just go with a simple glazed donut. Simplicity is best sometimes and Spalding's puts gimmicky trendy donut joints to shame.