Clean the squid by removing the tentacles, quill, guts, and skin.
Roughly chop half of the tentacles and set them aside.
Preheat the oven to 180°C and oil a large baking dish.
Fry garlic, anchovies, and capers in olive oil until anchovies dissolve.
Add chopped tentacles and stir-fry for five minutes before adding wine to evaporate.
Cool the mixture then stir in bread, pine nuts, lemon zest, and parsley.
Fill squid sacs with the mixture and tuck reserved tentacles into the ends.
Place squid in the dish, drizzle with oil, cover with foil, and bake for 45 minutes.
Remove foil and bake for another 15 minutes until golden-brown.
Combine radicchio and onion in a bowl with a dressing of oil and vinegar.
Serve the baked squid alongside the fresh salad.