Sautee onion, shallots, bacon, celery, carrots, potato together in oil. Add 1 ½ teaspoons of the salt. Cook over medium heat until the onions have softened and the mixture is very fragrant, about 10 to 15 minutes, stirring every few minutes. Meanwhile, whisk together the egg and the heavy cream in a small bowl and set it aside. Remove the pan from heat and add the vegetable stock, lemon juice, and lemon zest stirring to dissolve the brown bits at the bottom. Then add the egg and cream mixture, parsley, and thyme and stir until combined. Leave to cool to room temperature.

Grease a 9-inch pie pan and set it aside. Whisk the egg with vinegar and 3 tablespoons of ice water and set aside. Follow instructions below, depending on if you want to make the crust by hand, or if you want to use a food processor.

MANUAL METHOD: Mix together the flour, sugar, salt, garlic powder, and cream of tartar in a large wide bowl. Using a box grater, grate the butter using the large hole setting of the grater above the bowl, stopping to stir with a fork and coat the butter bits in the flour mixture every 10 seconds or so. When all the butter is in, pinch the mixture together with your fingertips until it resembles the texture of damp sand. Add the water, a tablespoon at a time, mixing it with a fork, until the dough just holds together when you squeeze a fistful of it in your hand.

FOOD PROCESSOR METHOD: In a small bowl, whisk together the egg, vinegar, and 3 tablespoons of the ice water. Set aside. Cut the butter into individual tablespoons and set aside. Place the flour, sugar, salt, garlic powder, and cream of tartar in the food processor and pulse a few times to mix together. Add the slices of butter and pulse until the butter is reduced to roughly pea-sized pieces. Run the machine while you add the egg mixture, letting it blend for 5 seconds after the liquid is added. Do NOT overmix. Add the remaining ice water, 1 tablespoon at a time, pulsing as you add it, until the dough just holds together. It shouldn't be too wet and sticky, nor should it be super crumbly.

Preheat the oven to 375 degrees Fahrenheit. Divide the dough into two equal portions, patting them into a rough circle shape about 1 inch thick. Cover one of them and place it in the refrigerator. On a lightly floured surface, roll out the other disc of dough until it is 1/8-inch thick and transfer it to the greased pie pan. Press the crust into the pan, trim off the excess leaving a 1-inch overhang (save the excess crust for decorations). Fold the 1-inch overhang under the edge of the crust all the way around.

Add the cooled filling to the pie, then lay the small fish on top like an asterisk shape, with the heads towards the edges of the pie and the tails overlapping in the center of the pie.

On a lightly floured surface, roll out the smaller quantity of dough until it is 1/8-inch thick. Cover the pie with the rolled out dough and cut little holes above where the heads are, then gently reach through the hole and pull the fish heads through so they’re poking out a bit. Press the edges of the crust edges together, and lightly brush the exposed pastry all over with the egg wash. Bake until deeply golden, about 45 minutes to 1 hour. Allow to cool for 20 minutes before slicing and serving