Place the calamari in a bowl with the buttermilk and stir well to combine.
Cover the bowl and place in the fridge for at least 30 minutes, but longer if you have time.
Heat three to four inches of oil in a large, deep pot and bring to a temperature of 190C.
Place the flour, salt, paprika, pepper and garlic powder into a medium bowl and stir well to combine.
Remove each piece of squid from the buttermilk and dredge into the flour, repeating the process until all pieces are evenly coated.