To prepare the chicken, drizzle 1 tablespoon extra-virgin olive oil into a large baking dish (at least 9-by- 12 inches). Add the sweet potato and onion slices, season with salt and pepper, and toss them in the oil.
Arrange the potato and onion slices in a single layer in the base of the dish. Place the lemon slices over them.
In a small bowl, whisk together the lemon juice, Worcestershire sauce, onion powder and thyme. Drizzle this mixture all over the chicken and rub into the top and underside of the chicken, coating it as much as you can.
Place the seasoned chicken, skin side up, in the center of the baking dish.
To prepare the rice, rinse the rice under cold running water and drain. Transfer to a small bowl and stir in the olive oil, turmeric, lemon zest, 1/2 teaspoon salt and 1/4 teaspoon pepper.
Scatter the rice around the chicken in the baking dish.
Pour the boiling water directly over the scattered rice (but not over the chicken). Cover the dish tightly with aluminum foil and bake in the oven for 45 minutes.
Remove from the oven and uncover. Return to the oven to cook until crispy, 30 minutes longer.