Clean the squid if need be and separate the tentacles from the body.
Mince the squid tentacles as finely as you can manage.
Heat olive oil in a skillet and add the garlic and anchovy. When the garlic is just beginning to give off its aroma, add the tentacles and give them a good stir. Pour over the wine and let simmer for a few minutes.
Add the bread (or breadcrumbs), olives, capers, parsley, plus the raisins and pine nuts if using. Give everything a turn, and keep stirring until you have a smooth, soft but compact mixture that comes away from the bottom of the pot. Add a bit more wine if it looks a bit dry or some breadcrumbs if it looks too loose. Taste and adjust for seasoning, then transfer to a mixing bowl and let the stuffing mixture cool.
When the ingredients have completely cooled, add the egg and mix well.
Fill the squid sacs with the stuffing mixture, either using a small spoon or—much easier—a pastry bag (see Notes). Leave some space at the open end and close the squid sacs with a toothpick.
In a sauté pan large enough to fit all the squid in one layer, gently sauté a garlic clove in olive oil. When it is just beginning to brown, remove it. Add the squid and turn them in the oil until they begin to stiffen and turn an opaque white. Then add the wine and let simmer for a few minutes.
Add the tomato, stir to mix it thoroughly into the cooking juices and cover. Let the squid braise until tender, probably a good 30-45 minutes (or longer if your squid is very large).
Serve the squid with their sauce while still warm but not piping hot.