Heat about 2 inches of oil in a heavy skillet or Dutch oven over medium-high heat until it reaches 350°F (175°C).

Place the onion rings in a medium bowl and pour the milk over them. Let them soak for 5 minutes to soften and ensure even coating.

In another bowl, whisk together the flour, salt, smoked paprika, and black pepper.

Drain the onions briefly, then toss them in the seasoned flour until each ring is thoroughly coated.

Working in batches, fry the coated onions for 2–3 minutes per side, or until they turn golden brown and crispy. Use a slotted spoon to transfer them to a paper towel–lined plate to drain excess oil.

Let the fried onions cool slightly before serving as a crunchy topping or snack.