Dice the tomatoes into 1/4-inch pieces and pat them dry with paper towels to remove excess moisture—this prevents the pinwheels from becoming soggy. Finely chop the olives into small, uniform pieces so they won't roll out when slicing. Crumble the feta cheese into small pieces for even distribution. Roughly chop the spinach if using larger leaves. Measure out the hummus and have all ingredients ready within arm's reach before assembling.

Lay one tortilla flat on a clean work surface. Spread about 6 tablespoons of hummus evenly across the tortilla, leaving a 1/2-inch border around the edges to prevent filling from squishing out. Distribute half of each filling ingredient (feta, tomato, olives, and spinach) across the hummus in an even layer. I like to sprinkle the oregano at this point—it adds a Mediterranean flavor boost that ties everything together. Starting from one edge, roll the tortilla tightly, keeping the fillings compact as you go. Repeat with the second tortilla.

Wrap each tortilla roll tightly in plastic wrap or parchment paper to hold its shape and prevent drying out. Refrigerate for at least 30 minutes, though up to 2 hours is ideal—the cold helps the filling set and makes the rolls much easier to slice cleanly without the filling sliding out. This chill time is crucial for getting clean, professional-looking pinwheels.

Remove the rolls from the refrigerator and unwrap them carefully. Using a sharp serrated knife, slice each roll into 8 pieces with a gentle sawing motion—I find a light touch works better than pushing down hard, as it prevents the filling from squishing out. If the rolls are very cold, a thin sharp knife dipped in warm water between cuts helps too. Arrange the pinwheels upright on a serving plate and serve immediately.