Step 1

Heat oil in a large skillet, preferably cast iron (you’ll need a lid), over medium-high heat. Add Jerusalem artichokes and ¼ cup water and season with salt and pepper. Cover and cook, stirring occasionally, until Jerusalem artichokes are fork-tender, 8–10 minutes.

Step 2

Uncover skillet and cook, stirring occasionally, until water is evaporated and Jerusalem artichokes begin to brown and crisp, 8–10 minutes longer; transfer to a platter.

Step 3

Add rosemary and butter to skillet and cook, stirring often, until butter foams, then browns, about 4 minutes.

Step 4

Remove skillet from heat and stir in vinegar, scraping up any browned bits. Spoon brown butter sauce and rosemary over Jerusalem artichokes.