Nutrition per serving may change if servings are adjusted.
Nonstick cooking spray
¼ cup refrigerated or frozen egg product, thawed
2 tablespoons buttermilk
¾ cup panko breadcrumbs
¼ teaspoon Cajun seasoning, blackened seasoning, or barbeque seasoning
1 large sweet onion (such as Vidalia or Walla Walla), cut into ¼-inch-thick slices and separated into rings
Preheat oven to 450°F. Lightly coat an extra-large baking sheet with nonstick cooking spray; set aside (see Tip). In a shallow dish, combine egg and buttermilk. In a small bowl, combine panko and Cajun seasoning. Transfer about one-third of the panko mixture to a shallow dish.
Dip the onion rings, one at a time, in buttermilk mixture, turning to coat and allowing excess to drip off. Dip onion rings in panko mixture, turning to coat (see Tip). Place onion rings in a single layer on the prepared baking sheet (you can place smaller onion rings inside larger ones as long as they don't touch). Add more of the panko mixture to the shallow dish as needed.
Bake for 12 to 15 minutes or until the onions are tender and the coating is crisp and golden.
Tips: If you don't have an extra-large baking sheet, use two large baking sheets and reverse the positions of the sheets halfway through baking.
Once the crumbs become wet, they do not cling to the onions as well so use only part of the panko mixture at a time.