Pre-heat the oven to 220C/200C Fan/ Gas 7
Start by pickling the onion. Place the ingredients into a small saucepan, gently heat until almost boiling. Turn off the heat and leave to sit for 20 minutes.
Prepare the cauliflower by mixing the oil and cumin a bowl, adding a pinch of salt and rub all over the cauliflower – for a more intense flavour let the cauliflower marinade for a couple of hours.
Place the cauliflower on a lined baking tray and bake for 20-25 minutes (depending on the size and shape of the cauliflower). To test if it’s cooked a cutlery knife should easily penetrate through the centre. Once cooked, turn off the oven and leave the cauliflower inside to keep warm in case you are still finishing off the other components.
Whilst the cauliflower is roasting, cook the lentils by placing them and the water in a small saucepan over a high heat and bring to the boil. Reduce to a medium heat and cover with a tight fitting lid and simmer for 20 minutes or until just tender. Drain.
Transfer the cooked lentils to a medium bowl, add the herbs, seeds, olive oil, lemon juice, herbs and season with salt and pepper, stir to combine.
For the satay sauce, simply place all the ingredients into a food processor and blend to create a relatively smooth, spoonable sauce.
To plate, place a handful of watercress on the plate, serve a large spoonful of lentils, add a portion of slice cauliflower, top with sauce and garnish with a few pickled onions.