Heat the oven to 425.
On a parchment lined rimmed metal baking sheet, toss the sweet potatoes in enough olive oil to lightly coat.
Roast for 20 minutes, then flip and roast for another 15 minutes or until tender. Set aside.
Increase the oven temperature to 450.
On the same parchment lined baking sheet, carefully toss the kale in enough oil to lightly coat.
Roast for 6 minutes or until crispy along the edges.
While the kale is cooking, whisk together the tahini, water, lemon juice, cayenne, pepper and salt until combined. Taste and adjust the ingredient amounts to your liking.
Scoop the cooked rice into a bowl, then top with the sweet potato, kale, avocado, sauce and pepitas. Season with salt and pepper, and serve with lemon wedges.