Put a large pan of salted water on to boil. Pour the tamari into a dish. Grate in the zest from the lemon. Squeeze in the juice from one half. Peel and grate in one garlic clove. Add 1 tsp each cumin and oregano and ½ tsp cayenne (the cayenne is spicy, so use less or more depending on how hot you want your final dish). Stir to mix together.

Add the chicken to the marinade. Turn to coat it all over. Set aside to soak.

Scrub the potatoes and chop them into chunks around 2cm across. When the water in the pan is boiling, add the potatoes. Turn the heat down a little and simmer for 15 mins till the potatoes are tender when pressed with a fork.

While the potatoes simmer, finely chop the parsley leaves and stalks. Pop them in a bowl. Peel and grate or crush the remaining garlic clove and add to the parsley. Finely chop the chilli, discarding the seeds and white pith for less heat. Add to the bowl with a pinch of salt and pepper. Stir in the crème fraîche. Set aside.

Pick any large stalks out of the watercress. Pop it in a bowl. Set to one side.

Warm a griddle or frying pan over a high heat for 2 mins. Add ½ tbsp oil and the chicken. Griddle for 10-12 mins, turning the chicken every so often, till it's lightly charred and cooked through - there should be no pink meat if you cut through the thickest part of the chicken fillets. Take out of the pan and pop on a plate. Loosely cover with foil and set aside to rest.

Add the cherry tomatoes to the pan with ½ tbsp oil and griddle for 5 mins, turning, till the tomatoes are soft and bursting.

The potatoes should be ready by now. Drain them, then return to the pan. Use a masher to gently squash the potatoes so they are crushed and break. Add half the crème fraîche sauce and toss to mix.

Serve the chicken with the crushed potatoes, griddled chicken, tomatoes, watercress and the remaining crème fraîche sauce.