Mix chicken pieces with yogurt, 1 tablespoon olive oil, half the garlic, all the spices, salt, pepper, and lemon juice in a bowl. Let marinate for at least 20 minutes.
Heat remaining olive oil in a large heavy-bottomed pot over medium-high heat. Add marinated chicken and sear for 3 minutes per side until golden. Remove to a plate.
Reduce heat to medium. Add diced onion and cook until soft and golden, about 5 minutes. Add remaining garlic and cook 1 minute more.
Add rinsed rice to the pot and stir for 2 minutes to coat grains in the spiced oil.
Pour in chicken stock and stir well. Bring to a boil, then nestle chicken pieces back into the rice. Reduce heat to low, cover tightly, and simmer for 18 minutes without opening the lid.
Turn off heat and let rest covered for 10 minutes. Fluff with a fork and garnish with fresh parsley and toasted nuts before serving.
