01 - Combine calamari rings with buttermilk, salt, and black pepper in a bowl. Cover and refrigerate for 15 minutes.
02 - In a shallow dish, mix all-purpose flour, cornmeal, paprika, garlic powder, and cayenne pepper.
03 - Heat vegetable oil in a deep skillet or heavy-bottomed pot to 350°F (180°C).
04 - In a saucepan, warm olive oil over medium heat. Add minced garlic and sauté for 30 seconds. Stir in crushed tomatoes, oregano, basil, sugar, salt, and pepper. Simmer uncovered for 10–12 minutes, stirring occasionally. Adjust seasoning as needed.
05 - Remove calamari from buttermilk, allowing excess to drip off. Coat thoroughly with the breading mixture.
06 - Fry calamari in batches without overcrowding for 1½ to 2 minutes until golden and crisp. Remove with a slotted spoon and drain on paper towels.
07 - Serve calamari immediately alongside warm marinara sauce, garnished with fresh parsley and lemon wedges.