01 - Combine calamari rings with buttermilk, salt, and pepper in a bowl. Cover and refrigerate for at least 15 minutes to tenderize.
02 - Heat olive oil in a saucepan over medium heat. Add minced garlic and sauté until fragrant, about 1 minute.
03 - Add crushed tomatoes, oregano, basil, sugar, salt, and pepper. Simmer uncovered for 10–15 minutes, stirring occasionally. Adjust seasoning to taste and set aside.
04 - In a shallow dish, whisk together flour, cornmeal, garlic powder, smoked paprika, and cayenne pepper until well combined.
05 - Heat vegetable oil in a deep fryer or large, heavy-bottomed pot to 350°F.
06 - Remove calamari from buttermilk, allowing excess to drip off. Dredge rings in the flour mixture, pressing gently to ensure even coating.
07 - Fry calamari in batches for 1–2 minutes or until golden and crispy. Do not overcrowd the pot to maintain oil temperature.
08 - Remove with a slotted spoon and drain on paper towels. Serve immediately with warm marinara sauce, lemon wedges, and fresh parsley garnish.