Ingredients
1 cup plus 2 tablespoons all-purpose flour
1 teaspoon ground cumin
Pinch of cayenne pepper
1 teaspoon coarse salt, plus more for seasoning
3/4 cup buttermilk
3/4 cup beer
1 large egg
4 cups peanut oil
2 large white onions (about 2 pounds), sliced crosswise 1/2 inch thick and separated into rings
Preparation
Combine flour, cumin, cayenne, and 1 teaspoon salt in a medium bowl. Slowly whisk in buttermilk, beer, and egg until smooth. Let batter stand 15 minutes.
In a large saucepan, heat oil over medium-high heat until a deep-fry thermometer registers 375 degrees. Working in batches, dip onion slices in batter, turning to coat. Gently drop slices into hot oil. Cook, turning rings once, until golden brown, about 2 minutes. (Adjust heat between batches as necessary to keep oil at a steady temperature.)
Use a slotted spoon to transfer rings to a paper-towel-lined baking sheet to drain. Season immediately with salt.
