01 - Place the calamari rings in a bowl, cover with buttermilk, and season with salt and pepper. Let marinate for 15 minutes in the refrigerator.
02 - Heat olive oil in a saucepan over medium heat. Add minced garlic and sauté until fragrant, about 30 seconds. Stir in crushed tomatoes, oregano, basil, red pepper flakes, salt, and pepper. Simmer for 10–12 minutes, stirring occasionally. Add sugar if desired. Keep warm.
03 - In a shallow bowl, mix flour, cornmeal, paprika, and garlic powder until well combined.
04 - Heat oil in a deep fryer or large pot to 350°F.
05 - Remove calamari from buttermilk, shaking off excess. Dredge rings in the flour mixture, ensuring even coating.
06 - Fry calamari in batches without overcrowding for 1–2 minutes, until golden and crispy. Remove with a slotted spoon and drain on paper towels. Season with salt immediately.
07 - Serve calamari hot with marinara sauce on the side. Garnish with lemon wedges and chopped parsley.