OK, actually it was in aluminum foil, not parchment paper as "en papillote" technically indicates. I took this whole red snapper (a little over 2 lbs I think), scored it three times on each side, salted, peppered, and oiled it, stuffed it with thyme, onion slices, minced garlic, lemon slices, and parsley, sprinkled more of the stuffing material all over along with some julienned carrots, and cooked it at 400 for around 25 minutes. Got the fish from Citarella on the Upper West Side, and it looked pretty fresh. It tasted good, but the texture was sort of mushy. So my question is: Was it an execution problem, or is this not the best fish for this method, or would it have been better if the fish was fresher, or is this just the way this comes out such that it shouldn't be regarded as a failing? Just in hunting for recipes, I came across more that called for roasting a whole snapper than anything, and I wonder if that more drying method might be better for this fish and others of its kind.