1. Preheat oven to 375°F (190°C).

2. Rinse 1 cup of basmati rice in cold water until the water runs clear. Set aside.

3. In a large bowl, mix together 1/2 cup of plain yogurt, 1 teaspoon of salt, 1/2 teaspoon of pepper, 1 teaspoon of garlic powder, 1 teaspoon of turmeric, and 1 teaspoon of cumin. Add in diced chicken breast and toss until well coated.

4. Heat up 2 tablespoons of vegetable oil in a large skillet over medium-high heat. Sauté finely chopped onion until translucent.

5. Add marinated chicken to the skillet and cook for about 5-7 minutes or until lightly browned.

6. Add in diced tomatoes and stir for another minute.

7. Transfer chicken mixture into a baking dish. Spread rinsed basmati rice evenly on top of the chicken mixture.

8. Add in 2 cups of water into the baking dish. Cover tightly with foil.

9. Bake for about 30-35 minutes or until the rice is fully cooked and all liquid has been absorbed.

10. Let it cool for a few minutes before serving.