Mix the shallot, onion, spices, including the saffron, into a bowl. Add the olive oil and mix well. Place shrimp into this marinade mixture, cover, and let stand for 2 hours. Melt the butter and set aside. Place shrimp under the broiler for 3 minutes per side. Mix the maindade drippings fro the shrimp with the remaining marinade in the bowl. Put warm rice on dishes. Serve shrimp over the rice. Pour the marinade mixture] over the shrimp and rice. Serve!