01 - In a bowl, toss calamari rings with buttermilk, salt, and black pepper. Cover and refrigerate for 15 minutes.
02 - In a shallow dish, combine flour, cornmeal, paprika, garlic powder, and cayenne pepper.
03 - Heat vegetable oil in a deep skillet or heavy-bottomed pot to 350°F.
04 - In a small saucepan, warm olive oil over medium heat. Add garlic and sauté for 30 seconds. Stir in crushed tomatoes, oregano, basil, sugar, salt, and pepper. Simmer uncovered for 10 to 12 minutes, stirring occasionally. Adjust seasoning as needed.
05 - Remove calamari from buttermilk, allowing excess to drip off. Dredge each piece thoroughly in the flour 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 with warm marinara sauce, garnished with parsley and lemon wedges.