Cut onion into rings and discard the peel. Separate all rings from each other. 

In a large bowl, add garlic powder, paprika, salt, black pepper and milk and combine. 

Add egg, 1 cup of the all purpose flour and the water to the milk mixture and whisk to incorporate fully into the batter. Add the water slowly because you may need less than 1 cup. You want a pancake batter consistency. 

In another bowl, add your final 1/2 cup of all purpose flour. 

Start heating up your peanut oil in a medium pan/pot over medium high heat. You want your oil to be at least two inches deep in the pot. You are shooting for 350 degrees F. If you do not have a thermometer, when your oil has been heating up for 8 to 10 minutes add a tiny pinch of flour and sprinkle it onto the oil. If it immediately starts to bubble and fry, then your oil is hot enough. 

Working in batches, add each onion ring first into the ap flour to fully coat and then add to the batter. When your oil is hot enough add your battered rings into the hot oil. 

Fry each batch of rings for 3 to 4 minutes or until they are golden brown. 

When golden brown, remove your onion rings to a paper towel lined sheet pan. 

Keep working through your batches of onion rings until all are fried.