just made this last night. i made 2 portions and used 420g potato, 2 salmon, 1x 160g bag baby spinach. made my own spice paste for the salmon and didn't add cream at the end, served w a lemon yoghurt. pretty good. takes about an hour and nice that it all finishes in one tray in the oven.
i think i'd just salt mine a little bit more and use 250g potato pp. you could maybe add another veggie like peas?
