Oven Fried Onion Rings with Chipotle Ketchup

olive or vegetable oil, for greasing pans

plus 2 tablespoons flour

sea or Kosher salt and fresh black pepper

egg

milk

seasoned panko crumbs (like Progresso)

seasoned Italian bread crumbs

large yellow or sweet onions, cut into 1/4 to 1/2 inch rings

organic ketchup

+ 1/2 teaspoons chopped chipotle chile in adobo plus 1 teaspoon of the sauce

balsamic or white vinegar