Preheat the oven to 425°F.
In a small bowl, mix together 1 tablespoon of the oil, the chili powder, garlic powder, smoked paprika, salt, and black pepper. Set aside.
Place the chickpeas on the prepared sheet pan and pat dry with a paper towel. Toss with the oil until fully coated. Push them to one side of the pan and place the sweet potatoes on the other. Coat the sweet potatoes with the remaining up to 1 tablespoon oil. Sprinkle with salt and turn them cut side down on the pan.
Bake until the sweet potatoes are fork-tender and the chickpeas are crispy, 28 to 30 minutes.
Meanwhile, in a small bowl, whisk together the Buffalo hot sauce and tahini until smooth. Set aside.
To serve, flip the sweet potatoes cut side up, and mash the insides with a fork. Evenly divide the crispy chickpeas among the potato halves. Place two halves on each plate and drizzle with the Buffalo/tahini sauce. Garnish with parsley and a squeeze of lemon.