Slice onions into thick 1/2-inch rings and separate them. Slice jalapeños into thin rounds.

Mix softened cream cheese, cheddar cheese, garlic powder, and black pepper in a bowl until combined.

Place onion rings on a parchment-lined baking sheet. Fill each ring with the cheese mixture, then press a jalapeño slice into the center.

Freeze the stuffed rings for at least 1 hour until solid.

Set up 3 bowls: one with flour, one with beaten eggs, and one with panko breadcrumbs.

Heat oil in a deep pot to 375°F (190°C).

Dredge frozen rings in flour, dip in egg, then coat thoroughly in panko breadcrumbs.

Fry in batches for 2-3 minutes until golden brown. Drain on a wire rack and garnish with parsley.