In a medium heatproof bowl, submerge the chiles in boiling water. Soak until softened, about 10 min.
Drain the soaked chiles, reserving the liquid, and transfer to a blender. Add the onion, garlic, vinegar, oregano, 1/4 cup chile liquid, and chipotle in adobo. Blend until smooth. Set aside.
Meanwhile, heat a large high-sided skillet over medium-high, and add 2 Tbsp. oil and half the carrots. Cook, turning a few times until carrots are golden in places, about 5 min. Transfer carrots to a plate. Repeat with the remaining carrots.
Scrape the chile puree into the empty skillet, and pour in the remaining 4 Tbsp. oil. Return the skillet to medium-high heat. Cook the chile puree, stirring, until mixture darkens and thickens, about 3 min. Stir in 1/2 cup chile liquid and the chickpeas, and return the carrots to the pan. Season with salt and pepper.
Cover the skillet. Reduce heat to medium-low, and simmer until carrots are crisp tender, about 7 min.
In a medium bowl, toss together the radish, avocado, pumpkin seeds, and tarragon with lime juice. Sprinkle radish salad over carrots and chickpeas. Serve with warm tortillas.
Recipe by Laura Rege.