01 -
Combine sourdough discard, warm water, yeast, sugar, flour, salt, and olive oil in a large bowl. Knead until a soft dough forms, approximately 8 to 10 minutes.
02 -
Cover the dough and let it rise in a warm environment until doubled in size, approximately 1 to 2 hours.
03 -
Set the oven temperature to 190°C and line a baking sheet with parchment paper.
04 -
On a lightly floured surface, roll the dough into a rectangle about 6 mm thick.
05 -
Evenly layer salami, pepperoni, and ham over the dough, leaving a small border. Sprinkle mozzarella, Parmesan, and Italian seasoning on top.
06 -
Carefully roll the dough lengthwise into a log, tucking the sides in to contain the filling. Place the log seam side down on the prepared baking sheet.
07 -
Brush the top with beaten egg to promote browning. Optionally, cut small slits on top to release steam during baking.
08 -
Bake in the preheated oven for 30 to 35 minutes until the crust is golden brown and crisp.
09 -
Allow to cool briefly before slicing. Serve warm, optionally accompanied by marinara sauce.