Preheat your oven to 350 degrees.

Roll out your first pie crust and put it in a deep dish 9 inch pie pan. Trim the dough to edge of the pie pan and set aside.

In a large sauce pan, melt the butter. Once melted, add the salt, old bay seasoning, salt, garlic, and mushrooms. Cook until the mushrooms are tender. Stir in the flour.

Very slowly, whisk in the wine, about a tablespoon at a time, until fully combined. Working just as slowly, add the half and half. Once it is fully combined, stir in the parmesan, baby onions, and peas.

Finally, stir in the cooked shrimp. The mixture will be very thick.

Pour into the prepared pie crust and level off so it is as even as possible.

Top with the remaining pie crust. Trim the crust so about a half an inch hangs off the edge. Fold the pie crust under the bottom crust. Brush the crust with the whisked egg white. Cut a few holes in the top of the crust and bake for 40 to 45 minutes or until the crust is golden brown. Let stand 10 minutes before cutting and serving.