Pop the bulgar wheat in a bowl with a pinch of salt and pepper. Pour in 250 ml boiling water. Cover with cling film or a plate. Set aside to soak.
Halve the courgette horizontally. Slice each half into thick slices. Peel and slice the onions into thin wedges. Pop the veg in a bowl. Season. Turn the veg to coat in the seasoning.
Bring a pan of water to the boil. Halve the squashes. Scoop out the seeds. Slice the squashes into wedges around 1 cm thick. Add to the pan of boiling water and simmer for 2 mins. Drain well. Cool under cold running water. Slice the skin off the squashes.
Slice each chicken breast in half horizontally to make four flat, thin steaks. Stir a good pinch of harissa into 1 tbsp oil and brush all over the chicken steaks. Set your oven to its lowest temperature.
Heat a griddle pan till it’s hot. Add the chicken steaks (in batches if you need to). Fry for 3-4 mins on each side till charred and cooked through. Pop on a plate. Cover with foil. Put in the oven to keep warm.
Add ½ tbsp oil to the griddle pan. Fry the squash for 5 mins till it’s charred, turning once or twice. Transfer to a bowl. Bung in the oven to keep warm.
Add ½ tbsp oil to the griddle pan. Fry the courgette and onions in batches for 2-3 mins till golden on both sides. Add to the squash.
Finely grate or pare the zest from the lemon. Mix into the yogurt with a pinch of harissa. Juice the lemon. Stir it into the bulgar wheat. Serve the chicken with the griddled veg and bulgar wheat.