In a saute pan, heat the olive oil and butter. When the pan is smoking hot, add the lobster shells. Saute the shells for 2-3 minutes, or until bright red. Add the shallots and garlic and saute for 1 minute. Stir in the tomato puree. Flambe the brandy. Pour in the shrimp stock and white wine. Season with parsley, salt, and pepper. Bring the liquid up to a boil. Simmer for 15 minutes. Remove from heat and strain through a fine chinoise into a sauce pot. Whisk in the cream and bring up to a boil. Reduce to a simmer. Simmer for 2-3 minutes. Mount in the 3 tablespoons butter. Season with the salt and cayenne.