Trim the root end of each onion and peel off the outer skin. Carefully cut a crisscross pattern into each onion, starting about half an inch from the root, going almost all the way through but keeping the base intact.

In a bowl, mix flour, paprika, garlic powder, salt, and pepper. In another bowl, whisk eggs and milk. In a third bowl, place panko breadcrumbs. Dredge each onion in the flour mixture, then dip in the egg wash, and finally coat thoroughly with panko, making sure the petals are well-covered.

Heat vegetable oil in a deep pot or Dutch oven to 350°F (175°C). Carefully place one or two onions in the hot oil and fry for 5-7 minutes, or until golden brown and crispy, turning occasionally to ensure even cooking. Remove from oil and place on a wire rack to drain.

While onions are frying, combine all dipping sauce ingredients in a small bowl and mix well.

Serve the crispy mini bloomin onions immediately with the prepared dipping sauce.