Combine the Flour, Baking Powder, Salt, Black Pepper, and Red Pepper in a bowl. Add the Beer and Vanilla and stir to make batter. Once mixed cover and let stand 30 to 50 minutes.
Next separate the Egg Whites into a bowl. Using an electric mixer beat the Egg Whites until soft peaks form. Fold Egg Whites into the batter.
Place the Bread Crumbs into a separate dish. Dip the Onion slices in the batter, then dredge through the Bread Crumbs and place in a single layer, on wax paper lined cookie sheet. Use wax paper to separate the layers. As soon as possible put the cookie sheet in the freezer. Freeze rings for at least 1 hour. After 1 hour place rings in an air tight container for longer storage time; they can be frozen for up to 3 months.
Remove rings and fry in 375 degree soy or peanut oil for appox. 2 minutes. For more even frying flip the rings. Fry in small batches, being careful not to crowd the pan.
*For a slightly spicy taste double the Red Pepper.
**For spicy taste that will stand up to the Ranch or other dairy based dips, double the Red Pepper and add 1/8 cup Sriracha sauce to the batter.