Preheat The Oven & Prep Your Station. To start, preheat oven temperature to 400 degrees F. Line a cookie sheet with parchment paper, then cut a large square of parchment paper for rolling out the dough. (It'll need to be at least 10 inches x 16 inches!)
Mix Up Garlic Butter & Egg Wash. In a small bowl, combine melted butter, dried parsley, garlic powder, and salt. In another small bowl, combine egg and 1 Tablespoon water. Whisk until smooth then set aside.
Divide & Roll The Dough. Divide the pizza dough in half (so you have two 1-pound balls of dough). Place one ball of dough on your parchment square and roll dough into a 10x16" rectangle.
Brush With Garlic Butter. Use a pastry brush to butter the dough with half of the garlic butter, spreading almost all the way to the edges of the rectangle.
Layer With Cheese & Toppings. Next, it's time to layer. Leave about 3 inches or so of empty space (just garlic butter & dough) on one long side of the rectangle. Layer cheese, followed by the meats onto the on the remaining 2/3 of the dough. (The toppings will shift during rolling, and leaving yourself this border on the side helps prevent them from spilling out.)
Roll Dough Into A Log. Starting at the long meats and cheese side of the rectangle, use the parchment paper to help you roll the dough towards the empty border, tucking the dough in as tightly as you can while you go. The toppings will shift some! When the dough is rolled into a log (seam side down!), tuck the short ends of the log underneath. Use the parchment paper to lift this stromboli onto your prepared sheet pan for baking.
Repeat With Second Stromboli. Repeat these steps, until you have two strombolis on the baking sheet (leave 2 inches or so between them so they can expand during baking!)
Brush With Egg Wash & Garnish. Use a pastry brush to brush a thin layer of egg wash onto the stromboli. Make sure to coat as much of the visible dough as you can so they brown evenly! (You will have leftover egg wash!) Sprinkle with parmesan cheese, parsley, flaky salt & pepper (& more garlic powder, if you like!).
Slit & Bake. Use a small sharp knife to make 4 shallow diagonal slits on the top of each stromboli. Bake at 400 degrees 30-35 minutes, or until the stromboli are golden brown and a thermometer inserted in the center of each stromboli reaches at least 200 degrees. (Keep in mind that fattier/greasier fillings can cause a little leaking during baking.)
Cool, Slice & Serve. Let the stromboli cool 5-10 minutes before cutting into slices with a serrated knife. (I usually get 12-14 slices from each stromboli) Serve warm with marinara sauce for dipping.