Heat oven to 400° F. Lightly coat a 9-inch pie plate with vegetable cooking spray. Peel, core, and cut pears into eighths and arrange them in the pie plate.Combine sugar, flour, eggs, milk, vanilla, butter, and salt in a blender. Pulse until smooth, about 30 seconds. Pour over the pears. Place in the oven and bake until springy to the touch, 25 to 30 minutes. Remove from oven. Heat broiler. Sprinkle the pancake with 1/2 teaspoon ground cinnamon and 2 tablespoons sugar. Broil until browned, about 1 minute. Serve warm.