Cook the orzo.
In a small frying pan over high heat, fry the haloumi until melting and beginning to turn golden, turning once.
In a large serving bowl stir the green herb dressing through the cooked orzo. Taste and season with salt and pepper as desired. Scatter with the cooked haloumi and sprinkle on the Parmesan.
Using a food processor or a stick blender, combine all the green herb dressing ingredients and process until thick.