Preheat your grill to high heat, approximately 450°F / 230°C, to ensure a fantastic sear.
Prepare the calamari by using a sharp knife to gently score the outside of the tubes in a crosshatch pattern, being careful not to cut all the way through.
Set the scored tubes and tentacles aside.
In a large mixing bowl, whisk together the olive oil, lemon juice, lemon zest, chopped oregano, minced garlic, sea salt, and black pepper to create the marinade.
Add the calamari to the bowl and toss thoroughly to ensure every piece is generously coated.
Cover and refrigerate for at least 30 minutes but no more than 1 hour. Any longer and the acid may start to toughen the calamari's texture.
Once ready to cook, thoroughly grease the hot grill grates with olive oil spray to prevent sticking.
Place the calamari on the grill in a single layer.
Cook for 90 seconds per side, just until the flesh turns opaque and develops light char marks.
Immediately remove the calamari from the grill and let it rest for a few minutes before serving. This allows the juices to redistribute, ensuring maximum tenderness.
Don't Over-Marinate: The acid in the lemon juice will 'cook' the calamari like ceviche if left too long. Stick to a 30-60 minute window for tender, not mushy, results.
Pat It Dry: For the best char marks, lift the calamari from the marinade and let any excess drip off. A drier surface sears better and prevents steaming.
