Preheat the oven to 425°F. Drain and rinse garbanzos in cold water until the water runs clear. Shake off any excess water, or use a salad spinner.
Spread beans on a clean dish towel or paper towel and pat dry, rolling the beans gently to absorb as much water as possible. Some of the outer skins will come off. Allow the beans to air dry for another 10-30 minutes.
Finely mince the chipotle pepper, or mash with a mortar and pestle. Mix in the olive oil and seasonings.
In a medium bowl, add the beans and seasoning mix. Toss lightly to coat. Spread on a baking sheet lined with parchment paper, providing plenty of space for the beans to roast.
Bake for 30-40 minutes. Every 10 minutes, shake the pan, and re-spread the beans. Watch the last 10 minutes of baking carefully, as they can quickly burn. At this time, they will be thoroughly browned, but still soft in the center when you break open one of the beans.
Turn off the oven, open the door slightly, and leave the pan inside as the oven cools for an additional 10-20 minutes to finish drying and creating a crispy outer surface. Serve warm or cool. Store any leftovers in a paper bag.
