In a large skillet, heat 1 tablespoon of olive oil over medium-high heat.
Add the chicken pieces, garlic powder, and pepper and cook until browned on all sides, about 7 minutes. Remove the chicken from the skillet and set it aside.
In the same skillet, add the remaining tablespoon of olive oil and 1 tablespoon of butter.
Add the onion and leeks. Cook until softened, about 5 minutes.
Stir in the Arborio rice and cook for an additional 2-3 minutes, allowing the rice to toast slightly.
Pour in 1 cup of the chicken bone broth and stir until it is mostly absorbed by the rice.
With one ladle at a time, continue adding the bone broth. Allow the liquid to be mostly absorbed before adding the next ladle. Continue this process until the rice is creamy and cooked to al dente, which usually takes about 15-20 minutes.
About halfway through the cooking process, add the cooked chicken pieces back to the risotto.
When the rice is cooked, stir in the grated Parmesan cheese and the remaining tablespoon of butter. Season with salt and pepper to taste.
Garnish the risotto with chopped fresh parsley. Serve immediately.