Chef John's Pizza Rustica

Craft the Crust: In a spacious bowl, meld the flour, salt, chilled butter, and olive oil. Employ a pastry cutter or your nimble fingertips to integrate the butter into the flour until the mixture resembles coarse breadcrumbs. Sculpt a well at the center, introduce the beaten egg, and agitate with a fork until harmonized. (Approximately 1 minute)

Introduce the cold water gradually, blending briefly with a fork. Transition to your hands, pressing the mixture into a unified sphere. Should the mixture appear parched, introduce additional water, a teaspoon at a time, until the dough coalesces. (Approximately 2-3 minutes)

Rest the Dough: Transfer the dough to a floured work surface, flatten into a disk, swathe in plastic wrap, and refrigerate for a minimum of 1 hour. (Resting Time: 1 hour +)

Prepare the Filling: While the dough slumbers, unite the drained ricotta cheese, mozzarella cheese, Pecorino Romano cheese, salt, pepper, beaten eggs, cooked Italian sausage, smoked ham, salami, and pepperoni in a capacious bowl. Blend thoroughly until impeccably combined; overmixing is of no concern. Enshroud and refrigerate until the moment of assembly. (Approximately 10-15 minutes)

Preheat and Prepare: Preheat the oven to a fervent 450 degrees F (230 degrees C). Anoint a 9-inch springform pan with olive oil and lightly dust with flour.

Roll the Crust: On a lightly floured stage, unfurl the dough. Reserve 1/3 for the upper crust. Roll the residual dough for the foundation crust, employing minimal flour, into a 15-inch circle, approximately 1/8 inch thick. Gently transfer the dough to the prepared pan, ensuring it nestles snugly into the bottom and ascends the sides, avoiding undue stretching. Excise any surplus dough, moisten with water, and employ to rectify any imperfections.

Fill the Crust: Decant the filling into the pan, pressing firmly against the edges to eradicate any latent air pockets, and level the summit.

Top the Pie: Roll the remnant dough into a circle slightly broader than the pan. Drape the top crust artfully over the filling, sealing it meticulously with the side edges.

Egg Wash Application: In a petite bowl, amalgamate the remaining egg with water to fashion an egg wash.

Adorn and Seal: Lavish the egg wash upon the dough's apex, ensuring comprehensive coverage. Trim any immoderate dough. Fold the side dough downwards from the pan's perimeter onto the upper crust, crimping the edges with your fingertips until impeccably sealed. Bestow a second coat of egg wash.

Bake to Perfection: Position in the epicenter of the preheated oven, promptly diminishing the heat to 350 degrees F (175 degrees C). Bake until the upper crust attains a resplendent golden-brown hue. (Approximately 1 hour 15 minutes)

Cool and Serve: Extricate from the oven and permit a 10-minute respite. Delicately detach the ring and allow an additional 15 minutes of cooling before partitioning into wedges. (Cooling Time: 25 minutes)