In a bowl, cover chickpeas with 2-3 inches of water. Allow to soak overnight.
Preheat oven to 400 degrees.
Drain chickpeas and return to bowl. In a small, lidded container, shake together the red wine vinegar, 1 teaspoon of the kosher salt, dijon mustard and lemon juice. Add the olive oil and shake again to combine. Add vinegar mixture to chickpeas and toss to coat. (I used a lidded bowl for this to avoid making a gigantic mess.)
Spread chickpeas out onto a half sheet pan. Roast for 60-65 minutes, stirring every 15 minutes, or until chickpeas are a dark golden color and are crunchy.
Return chickpeas to the bowl. Add the remaining 1/2 teaspoon of salt and 2 teaspoons of malt vinegar. Toss to coat; return chickpeas to sheet pan and allow to cool. Store in a zip-top bag or lidded container.
Notes
*The original recipe used red wine vinegar both in the dressing and at the end. I like the extra tang that malt vinegar gives at the end, which is why I chose to use it, but you could easily use red wine vinegar both times and they will still be delicious.Adapted from Good Eats 3: The Later Years