For best results, use an active starter that has recently peaked so the dough rises reliably and develops good flavor, and avoid overfilling with pepperoni and cheese so the loaf can still seal and rise without bursting. If your kitchen is cool, extend the bulk ferment and final proof rather than adding more starter, watching the dough’s volume and feel instead of the clock. You can adjust fillings with other cured meats or cheeses, but keep the total amount similar to prevent a dense loaf, and always let the bread cool sufficiently before slicing to maintain a nice structure and keep the melted cheese from oozing out.