1. Bring 5 cups water to a boil in medium saucepan. Add rice; boil 10 minutes. Drain. Rinse rice; drain.
2. Heat a medium, heavy-bottomed skillet over medium heat. Add 1 1/2 teaspoons oil to pan; swirl to coat. Add onion, and cook 5 minutes. Stir in 1 teaspoon cumin, 3/4 teaspoon salt, and turmeric; cook 1 minute. Combine rice, onion mixture, and yogurt in a bowl.
3. Return pan to medium-high heat. Add butter and 1 tablespoon oil to pan; swirl until butter melts. Add rice mixture to pan, lightly packing rice down. Reduce heat to medium-low. Wrap a clean, dry dish towel around the lid, tying it at the handle; place prepared lid on pan. Cook rice, covered, over medium-low heat 10 minutes (do not stir or uncover). Reduce temperature to low; cook an additional 20 minutes or until rice is tender on top and a golden crust forms on bottom.
4. Loosen the rice crust with a rubber spatula around the edges. Place a plate over the top of pan, and invert the rice onto plate, browned side up.
5. While rice cooks, preheat broiler to high.
6. Combine remaining 1 tablespoon oil, remaining 1/2 teaspoon cumin, sambal oelek, garlic, and coriander in a small bowl, stirring well. Scrape spice paste into a zip-top plastic bag. Add chicken to bag; seal. Toss to coat. Let stand 20 minutes. Remove chicken from bag; discard marinade. Sprinkle chicken evenly with remaining 1/4 teaspoon salt.
7. Place chicken, skin-side up, on a foil-lined broiler pan coated with cooking spray. Broil 8 minutes or until browned. Turn chicken over; broil an additional 4 minutes or until done. Serve with rice.