Preheat the oven to 425 degrees F (220 degrees C).

Place pizza crust on a pizza pan.

Bake in the preheated oven until just crisp, about 5 minutes.

Meanwhile, combine garlic, Dijon mustard, rosemary, and vinegar in a food processor or blender. With the blender on, drizzle in olive oil slowly until dressing is thickened. Quickly pulse in 1/4 cup blue cheese; season with salt and pepper.

Spread vinaigrette over pizza crust. Sprinkle remaining 1/4 cup blue cheese evenly over crust, followed by mozzarella cheese. Arrange sliced pears over cheese and sprinkle with walnuts.

Bake in the preheated oven until cheese is melted and bubbly, 7 to 10 minutes. Let cool slightly before cutting into slices.