Using a food processor, add the pine nuts and process until chopped fine. Add the rest of the pesto ingredients and blend until combined and smooth.
Toast the bagel thins in a toaster.
On each half, add 1 tablespoon of hummus, followed by 2 tablespoons pesto. Top with tomato, roasted red pepper, or arugula and sprinkle with salt and freshly ground black pepper. Makes 4 bagel halves (2 full bagels). Best served when bagels are still warm.