Heat the olive oil in a large saute pan over a medium flame. Split open the garlic clove by placing it on a cutting board and pressing down hard with the base of your hand or with the flat side of a knife. Add the garlic to the pan and cook until it starts to brown, about 2 minutes.
Add the onions and bay leaf, and cook slowly until the onions are light brown, about 10 minutes. Then reduce the heat to low and cook, stirring occasionally, until the onions are soft and tender (caramelized), about 20 minutes. If the onions start to get too dark, add 1/2 tablespoon of water. Remove them from the pan with a slotted spoon and set aside, leaving the oil in the pan.
Raise the heat to high and sprinkle a little salt on the oil. Add some of the squid, making sure you don't overcrowd the pan--you need to leave plenty of space between them so the heat remains high and the squid is sauteed, not boiled. Saute for 15 to 20 seconds on each side. Remove the squid from the pan and repeat the process with the remaining squid.
Return all the squid to the pan, add the caramelized onions and stir together. Pour in the wine and boil for around 20 seconds. Sprinkle with the parsley and serve.