01 - In a bowl, combine calamari rings with buttermilk, salt, and black pepper. Cover and refrigerate for 15 minutes.
02 - In a shallow dish, mix together 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 over medium heat, warm olive oil. Add minced 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 to taste.
05 - Remove calamari from buttermilk, allowing excess to drip off. Thoroughly dredge each piece in the flour mixture.
06 - Fry calamari in batches without overcrowding for 1½ to 2 minutes until golden and crispy. Remove with a slotted spoon and drain on paper towels.
07 - Serve the crispy calamari immediately alongside warm marinara sauce. Garnish with fresh parsley and lemon wedges, if desired.