01 -
Set oven temperature to 400°F (200°C) to preheat.
02 -
Melt unsalted butter in a large skillet over medium heat. Add onion, carrots, and celery; sauté until softened, approximately 5 to 7 minutes.
03 -
Sprinkle in all-purpose flour and cook, stirring for 1 minute. Gradually whisk in heavy cream, stirring until mixture is smooth and begins to thicken.
04 -
Fold in chopped lobster meat, frozen peas, thyme, parsley, lemon juice, salt, and pepper. Stir to combine thoroughly. Remove from heat and allow to cool slightly.
05 -
On a lightly floured surface, roll out the puff pastry or pie dough to cover your baking dish. Gently press the dough into the bottom and sides as needed.
06 -
Spread the lobster mixture evenly in the prepared baking dish.
07 -
Drape rolled pastry over the filling, sealing the edges firmly. Cut small slits in the surface for steam to escape and brush top evenly with beaten egg.
08 -
Place baking dish in preheated oven and cook for 25 to 30 minutes, or until crust is deeply golden and cooked through.
09 -
Remove from oven and permit to cool for 10 minutes before slicing.
10 -
Slice and serve warm.