Marinate diced chicken in 1/2 cup yogurt, cumin, cinnamon, and pinch of salt for at least 2 hours.
Preheat oven to 350°F Bring a medium pot of water to a boil. Add rice and simmer for 30 minutes; drain well.
Meanwhile, heat oil in a large ovenproof pot over medium high heat. Add chicken, and sauté until almost cooked through. Add garlic, onion, ginger, half of the cashews, 1/2 teaspoon salt and 1/4 teaspoon pepper and cook, stirring often and adding a splash of water when the mixture sticks to the pot, until deep golden brown and soft, about 15 minutes. Add remaining yogurt and curry powder and cook until thickened, 2 to 3 minutes more. (Depending on consistency, you may need to add a couple extra spoonfuls of yogurt at this time.) Stir in vegetables, broth, remaining 1/2 teaspoon salt and 1/4 teaspoon pepper, cover and simmer until vegetables are tender on the outside but not cooked through, about 5 minutes. Remove pot from heat and stir in frozen peas. â€¨â€¨Arrange hot, drained rice over vegetables, cover pot with foil and a tight-fitting lid and bake until rice and vegetables are tender, about 25 minutes. Uncover, carefully transfer contents of pot to a large bowl and toss together gently. Spoon into bowls and serve garnished with remaining cashews.