To make the marinade, place the garlic in the bowl of a food processor fitted with the metal blade and pulse until minced. Add the lemon juice, onion, parsley, wine, olive oil, salt, and pepper and process until finely chopped. Transfer the marinade to a large mixing bowl, add the chicken pieces, and toss to combine. Cover and refrigerate overnight.
In a small bowl, whisk together the flour, oregano, and baking powder. Remove the chicken from the refrigerator and leave it in the marinade. Add the flour mixture and stir to coat the chicken evenly. Discard any marinade remaining in the bowl.
In a large heavy skillet, heat 1/2 inch of vegetable oil over medium heat to 365˚F. Set a wire rack over a rimmed baking sheet.
Working in batches, carefully place 6 to 8 pieces of chicken in the oil. Fry, turning often, for 8 minutes, or until brown and juices run clear. Maintain a frying temperature of 340˚F to 350˚F. Drain the chicken on the wire rack. Repeat with the remaining pieces.
After all the meat is fried, turn off the heat. Line a plate with a paper towel. Place the sliced garlic in a metal strainer and slowly lower into the hot oil to fry for 10 to 15 seconds or until lightly browned. Quickly remove the strainer from the oil and drain garlic on the prepared plate.
Serve the chicken sprinkled with garlic and additional chopped parsley.