1.5 pounds onion – cut into 0.5-inch-thick slices, rings separated
1.5 cups all-purpose flour
0.5 cups cornstarch
1 tsp baking powder
0.5 tsp paprika
0.5 tsp black pepper
1.5 tsp kosher salt
12 ounces beer – chilled
2 quarts vegetable oil – for frying
Instructions
Peel and slice the onions into 0.5-inch-thick rounds, then separate into individual rings.
Place 0.5 cup of the all-purpose flour in a shallow dish for dredging; whisk the remaining 1 cup with the cornstarch, baking powder, paprika, black pepper, and 1 tsp of the kosher salt in a large bowl.
Pour in the chilled beer and whisk just until smooth and the consistency of heavy cream; a few small lumps are fine. Let the batter rest 10 minutes while you heat the oil.
Heat the vegetable oil in a deep, heavy pot to 365–375°F, with at least 2 inches of oil depth. Line a sheet pan with a wire rack or paper towels.
Pat the onion rings dry. Dredge a batch of rings in the flour set aside for dredging, shaking off excess so only a light dusting remains.
Working in batches, dip the floured rings into the batter, letting excess drip back into the bowl, then carefully lower into the hot oil. Fry 2–3 minutes, turning once, until deep golden and crisp; adjust heat to maintain 365–375°F and avoid crowding.
Transfer fried rings to the prepared rack and immediately sprinkle with the reserved 0.5 tsp salt. Return the oil to temperature between batches and repeat with remaining rings.
Serve hot and crisp within minutes for best texture.