1. Break up the onion slices into rings. Set aside.
2. Combine flour, baking powder, and salt, in a small bowl and mix well.
3. Dredge the onions on the flour mixture and set aside.
4. Meanwhile, make the batter by adding the egg and milk on the flour mixture and whisk.
5. Dip the onions on the batter and allow the extra batter to drip.
6. Place the breadcrumbs in a plastic bag or container and put-in the onions rings.
7. Heat a cooking pot and pour-in cooking oil.
8. When the oil is hot, deep-fry the onion until the color turns golden brown (usually 2 minutes or so).
9. Remove the onion rings from the cooking pot and place in a plate lined with paper towels, to absorb the excess oil.
10. Transfer to a serving plate and serve.
11. Share and enjoy!