Preheat the oven to 400ºF. Lightly oil a baking sheet.
Rub the fillets with the olive oil and season with salt and pepper.
In a small mixing bowl, toss the crabmeat and garlic together. Season with salt and pepper.
Cut a piece of parchment paper about 2 inches longer than the fish. Fold the paper in half lengthwise, then open it flat. Place the fish on one half of the paper. Spread the crabmeat mixture evenly over the fish. Fold the other parchment half over the fish and roll the edges to seal the fish tightly in the bag. The bag should be formed in the shape of the fish. Place the bag on the baking sheet and bake for 10 to 12 minutes.
In a small nonreactive saucepan, combine the lemon juice and shallots. Bring to a gentle boil and cook until the liquid reduces by half, about 3 minutes. Add the cold butter cubes, 2 to 3 at a time, and whisk until completely melted. Season with salt and pepper. Stir in the chopped parsley.
To serve, cut off the top of the bag and roll it back with a fork to expose the fish. Spoon the sauce over the fish and garnish with parsley sprigs.
Yield: 2 servings