Preheat oven to 450 degrees. Line a baking sheet with parchment paper.
In a shallow bowl, mix together the dairy free milk, vinegar, chickpea flour and cornmeal.
In another shallow bowl, mix together the panko, baking powder, paprika, garlic powder, Italian seasoning, salt, pepper, and optional red pepper flakes.
Slice onions into 1 inch thick strips and push apart the layers.
Dip onions in the wet batter, letting any excess drain off.
Coat in the breadcrumb mixture.
Place on baking sheet and repeat with remaining onion ring slices.
Bake for 25-30 minutes or until golden brown, flipping halfway.
Best if served right away.