Ingredients

• 1 cup buttermilk
• 1 cup all-purpose flour
• Kosher salt, freshly ground pepper
• 1 large red onion, sliced into 1/4-inch-thick rings
• 8 tablespoons (1 stick) unsalted butter

Instructions

1. Place buttermilk in a medium bowl. Place flour in another medium bowl; season with salt and pepper. Working in batches, toss onion rings in flour; shake off excess. Dip in buttermilk, letting excess drip back into bowl. Return to flour and toss to coat again; shake off excess.
2. Heat 4 Tbsp. butter in a large skillet over medium, stirring occasionally, until lightly browned and foaming. Add half of onion and cook, turning once, until golden brown and crisp, 8–10 minutes. Transfer to paper towels with tongs; season with salt and pepper. Repeat with remaining butter and onion.