01 - Organize all filling ingredients and set up a large shallow bowl filled with warm water for softening rice paper sheets.
02 - Submerge a single rice paper sheet in warm water for 5–10 seconds until pliable. Transfer to a clean, damp kitchen towel or cutting board.
03 - Spread approximately 1 teaspoon of pizza sauce in the center of the softened rice paper sheet.
04 - Arrange mozzarella, black olives, diced bell pepper, sliced mushrooms, and red onion over the sauce. Season with dried oregano and crushed red pepper flakes.
05 - Fold both sides of the rice paper toward the center, then roll tightly from bottom to top to completely enclose the filling, similar to a burrito or spring roll technique.
06 - Repeat the soaking, filling, and rolling process with the remaining 11 rice paper sheets and filling ingredients.
07 - Heat olive oil in a large nonstick skillet over medium heat. Place rolls seam-side down and cook for 2–3 minutes per side until golden brown and crispy. Cook in batches if needed to avoid overcrowding.
08 - Transfer rolls to a plate and let cool briefly. Serve with additional pizza sauce for dipping.