In a blender or food processor, combine the peas, basil, olive oil, parm, crushed red pepper, garlic, lemon juice and zest, and heavy pinch each of salt and pepper. Purée until mainly smooth.
In a large bowl, toss the cooked pasta, arugula, and mozzarella with the pesto until well combined. Taste and adjust the seasoning with salt and pepper, then serve.
