Place the chiles in a spice grinder and grind until fine.
Add the salt, lime zest and sugar. Pulse a few more times until well combined and set aside.
Spread the chickpeas in a single layer on paper towels and pat dry.
Heat 3/4 inch of oil in a heavy-bottomed shallow pot or small Dutch oven to 375 degrees F. Carefully add the chickpeas in small batches, about a cup per batch, to the oil. (The oil will bubble up for a few seconds.) Fry, stirring occasionally, until browned and crisp, 8 to 10 minutes per batch.
Transfer to a paper towel-lined tray and immediately sprinkle with some of the chile salt. Cool slightly and serve.
Chef's Note: The chickpeas can be fried 2 to 3 days ahead of time. Cool without the chile salt and store in a sealed plastic container. Before serving, spread in a single layer on a baking sheet and toast in a 400-degree F oven until sizzling and crispy. Season with the chile salt, cool and serve.
