Clean your squid, I will write a 101 topic on this if you are not sure. Remove the skin, pull out the clear bone, and turn inside out to thoroughly clean the inside, then turn right side out, place the squid on a plate and put in the fridge. Cut the tentacles off in front of the beak, discard the head. Photo shows the squid cleaned, I used 4 squid.
Heat your oven to 190° C (375° F), get out a 8x11 or 9x13 baking dish depending on number of squid you are using.
Dice the the tentacles and the shrimp (remember to remove the tails), place this in the bowl with the diced tomatoes, zest, ginger, parsley, and pepper. Mix well.
Heat the olive oil in a medium pan over medium heat, add the onions and salt and cook until the onions turn translucent, about 1 to 2 minutes, do not brown them, add the garlic and continue to cook for another minute. Remove from heat and put this into a medium mixing bowl and set aside to cool.
Once the onions and garlic are cool, add to the squid, shrimp mixture and mix well. Photo shows the stuffing mixed.
Using either a long ice tea spoon or a bag with a corner cut off, fill each squid with the mixture, do not over stuff them.
Place each filled squid in the baking dish.
Once all are filled, cover with tomato sauce of your choice (can be home made sauce or canned spaghetti sauce). Sprinkle with Parmesan cheese if desired.
Cover with foil and bake for 30 minutes. Photo shows foil removed after baking.
Serve over pasta of your choice.