Preheat the oven to 425°F (218°C) Place the drained and rinsed chickpeas on a clean kitchen towel (or paper towels) and pat dry. It is very important for the chickpeas to be as dry as possible before they hit the oven, otherwise they won't crisp up properly.
Place the chickpeas on a half sheet pan and drizzle them with the olive oil. Add the salt and freshly ground pepper, and toss until evenly distributed.
Roast for 15 minutes. Remove from the oven, and toss the chickpeas with a spatula or wooden spoon. Roast the chickpeas for an additional 10 minutes or until they are golden brown and crispy (but not too dry).
Drizzle the chickpeas with the vinegar, toss, and pop them back into the oven for another 30 seconds or so. Remove from the oven and allow to cool slightly before eating (the salt and vinegar flavor will be more pronounced when they are lukewarm, rather than piping hot out of the oven).
Best served within a few hours of roasting (preferably right after); they can also be stored in an airtight container for 1 to 2 days.