Cut the squash in half, then peel and scrape the seeds from each half. Cut into half-moon slices, a quarter-inch wide by about three inches long.

Place the olive oil and garlic into a medium sauté pan. Sauté the garlic over low heat until it is a deep golden brown; discard garlic. Raise the heat to medium-low and add squash slices in a single layer, making sure not to crowd. Fry the squash slices until they are golden brown and blistered; they will be tender, but still hold their shape. Cook in batches, transferring each batch to a platter when finished. When they are done, sprinkle with the mint.

There will still be olive oil in the pan—add the vinegar, sugar, salt and pepper. Raise heat to high and boil the mixture until it thickens slightly. Pour over the squash slices and let cool. Marinate for several hours before serving; may be refrigerated for several days.