Open your package of puff pastry and unroll until you have a flat circle of dough on a piece of parchment paper. (If you have rectangular dough, that will work too—you may just need to trim the edges when you fold.) Place on a baking sheet.

Mix together the tomato paste, anchovies, and garlic in a small bowl until well-incorporated. Then spread the paste down the middle of the circle of dough, making a rectangle about 4 inches wide and as tall as the length of the dough (leaving a finger's width at the top and bottom of the dough empty).

Layer half of the meat, half of the cheese, then the other half of the meat and other half of the cheese on top of the paste.

Then layer on the peppers, artichoke hearts, olives, fresh mozzarella, and pickled hot peppers.

Sprinkle with oregano and black pepper, then drizzle vinegar and olive oil over the filling. If the pastry has warmed up during this time, put the baking sheet back in the refrigerator to firm up.

When the pastry is cool, use a small knife to make diagonal slashes, 1 inch in width, down the length of each side (from filling to edge of circle). Take care to cut the same number of slashes on each side.

Now, fold the pastry at the top of the circle over the filling, and pull over the first strips on either side, overlapping slightly. The top of the pastry circle should be tucked in under the first strips.

Continue to pull over the strips on each side, latticing them as they come together over the filling. Try not to stretch them out as you work with them.

When you get to the bottom, fold up the bottom edge as you did the top, tucking it under the final two lattice strips. Your final stromboli should be around 5.5 x 11 inches (14 cm x 28 cm).

Chill in the refrigerator for at least 30 minutes, and up to 2 hours.

While stromboli is chilling, preheat the oven to 415 degrees F (210 Celsius). If you have a baking steel or stone, place that on the center rack to heat. If not, preheat a baking sheet.

When ready to bake, brush the stromboli with the egg wash, then sprinkle with parmesan cheese.

Place your baking sheet with stromboli on it onto the baking steel. Or, if you aren't using a baking steel, take the hot baking sheet out of the oven, and place the stromboli (on its parchment paper) on it.

Bake for 35-45 minutes, until filling is bubbling and pastry is browned.

Check on the stromboli 10 minutes early to make sure it is not overly dark. If it is browning too fast, tent with foil for the final minutes.

Let cool slightly before slicing, then serve warm or at room temperature.