Here's a few hints when buying calamari.
1. Buy it clean.
2. Buy it clean
3. Buy it clean
I know I've repeated myself but it's worth repeating. Those tiny creatures are tedious to clean and if you can purchase them cleaned already why wouldn't you.
You are still going to have to make sure that they are clean, you just won't have to spend hours cleaning them. Trust me on this, buy them clean, and if you're stuffing them buy them big!
I started off by soaking the calamari tubes and tentacles in milk for a few hours. The size on these said they were 5" - 8". (They cooked to a smaller size.)
I separated the tentacles from the tubes and I par boiled the tubes. (I don't know if this is correct but it helps the tubes to stay open while stuffing them) give the tubes a cold bath so they stop cooking. Set the tubes aside.
In a sauté pan with half a chopped onion, 2 cloves garlic, 1 tablespoon olive oil, 2 cups fresh spinach leaves, and 1 celery stalk chopped cook the tentacles with 5-6 extra large shrimp just until the shrimp turn pink. Take off the heat. Let the mixture cool a little.
This mixture will need to go into a food processor. I like to "pulse" it a few times so the mixture has a little chew to it and not completely smooth.
Season the mixture with salt and pepper to taste. Add a pinch of hot pepper flakes. The mixture will be moist. I added a small handful of seasoned breadcrumbs.
Now it's time to stuff.
If you have a pastry bag you may use it, or use a plastic ziplock and cut off one corner and fill the tubes. Or do it my way, get the baby spoons out! I fill them all the way.
Place them in a baking pan that has a basic tomato sauce*. Add a little white wine, add one can of red kidney beans, cover and bake for 10 minutes or until heated through.
*please use fresh tomato sauce and not something premade that tastes like "homemade". It will make a huge difference in flavor.
I served the stuffed calamari over very refreshing zucchini "spaghetti".