Heat the oven to 450 degrees.

Melt the butter over medium heat and swirl around the pan until the foam subsides and it browns and smells nutty. Be careful not to burn. Set aside off the heat.

Slice the potatoes with a mandolin or very sharp knife to be 1/8th of an inch thick.

Brush the bottom and sides of an 8 inch round pan with the browned butter.

Starting from the center, arrange the slices of sweet potato in a circular pattern with the slices slightly overlapping into one layer covering the bottom of the pan. Brush the slices with butter evenly.

Repeat with layers of sweet potato and butter until you run out of slices. Brush with remaining butter (it's okay to have some butter leftover).

Cover the potatoes with foil and press down evenly to compact the slices. Set a heavy ovenproof pan on top of the foil and put the pans into the oven for 30-40 minutes or until the potato is soft.

Take out of the oven, remove the top pan and the foil. Use a spatula or knife to run along the side of the pan to loosen. Set a serving plate on top of the pan and carefully flip over the pan.

Sprinkle the maple sugar evenly over the top of the sweet potatoes. Use a kitchen torch to brûlée the sugar (or flip sweet potatoes onto a sheet pan and broil under high heat to melt the sugar).

Let the sugar cool and sprinkle the salt generously over sweet potato Anna.