Wash and clean the calamari thoroughly. Carefully chop the tentacles into small pieces (but not too fine) and place them in a bowl. Zest one lemon over the tentacles, then squeeze in the juice from half the lemon. Add salt, mix well, and set aside to marinate.
In a large bowl, combine the breadcrumbs, Pecorino, chopped parsley, and pepper. Mix to combine. Zest one whole lemon into the bowl, then cut it in half and squeeze the juice from both halves. Squeeze the juice from the leftover half (in step 2)—so you have juice from 1½ lemons in total.
Crush one garlic clove, then add it to the bowl along with 1-2 Tbsp capers and 3 Tbsp of EVOO, then mix well. Add the marinated calamari tentacles and mix using a spoon until well combined. If the mixture is dry, add EVOO until it becomes moist and use your hands to mix once again.
Take each calamari tube and use a small spoon to fill it about one-third full with the breadcrumb mixture. Gently press the filling down with your finger so it’s compact, but not overstuffed.
Seal the calamari gently by pressing the open end together and secure it with a toothpick. Place each stuffed calamari into a baking dish lined with baking paper.
Drizzle a little EVOO over each stuffed calamari, then sprinkle some panko on top. Cut the cherry tomatoes in half directly over the baking tray, letting the juices fall in and drop the cherry tomatoes into the tray too, spreading them all over. Add one unpeeled clove of garlic to the tray.
Drizzle 3 tablespoons of EVOO over the cherry tomatoes. Season with salt and pepper. Bake at 180°C / 356°F for 40 minutes or until the calamari start to turn lightly golden.
Once baked, remove the stuffed calamari from the baking dish and using a potato masher, gently squash the roasted cherry tomatoes, allowing them to release their juice. You can add the garlic in too (after removing the skin), or remove it altogether. Add a drizzle of EVOO and a handful of fresh basil leaves, then mix really well to create a light tomato sauce to top each serve of calamari.