Recipe information
Yield
Serves 6 as a main course
Ingredients
Preparation
Step 1
Cover phyllo stack with overlapping sheets of plastic wrap and then a damp kitchen towel.
Step 2
Melt 4 tablespoons butter. Arrange 1 phyllo sheet on a work surface and brush with some melted butter. Arrange another sheet to overlap the first and form a 17-inch square and brush with butter. Continue layering with remaining 6 sheets and butter. Drape phyllo stack over a 10-inch tart pan with a removable bottom and fit phyllo into pan. Crumple overhang against inside edge of rim to create a ragged edge that stands about 1 inch above rim. Chill shell, loosely covered, until firm, at least 3 hours.
Step 3
Preheat oven to 375°F.
Step 4
Prick bottom of shell all over with a fork and bake in middle of oven until golden, about 15 minutes. Cool shell in pan on a rack. Shell may be made 1 day ahead and kept, covered, at cool room temperature.
Step 5
In a saucepan melt remaining 1 1/2 tablespoons butter over moderately low heat and whisk in flour. Cook roux, stirring, 3 minutes and whisk in milk and cream. Bring mixture to a boil, whisking constantly, and simmer, whisking occasionally, 3 minutes. Season mixture with salt and pepper and cool.
Step 6
Discard skin and bones from trout and break fish into small pieces. Separate eggs. In a food processor pulse together milk mixture, trout, yolks, horseradish, and dill until smooth and transfer to a large bowl.
Step 7
In another large bowl with an electric mixer beat whites with a pinch salt until they just hold stiff peaks. Stir one fourth whites into trout mixture to lighten and fold in remaining whites gently but thoroughly.
Step 8
Pour soufflé mixture into shell and run tip of a knife around edge of soufflé to aid rising. Bake soufflé on a baking sheet in lower third of oven until puffed and golden brown, about 25 minutes. Serve soufflé immediately.