Trim the aubergines and courgettes and cut into bite-size chunks. Peel and finely slice the onions. Peel and grate the garlic cloves. Separate the chard leaves and stalks. Finely slice the stalks and roughly chop the leaves.
Pour 1 tbsp oil into a large pan and bring to a high heat. Slide in the aubergine and sprinkle in a little salt and pepper. Fry for 5-6 mins, stirring occasionally, till well coloured on the outside and tender in the middle. Use a slotted spoon to transfer to a plate.
Pour another 1 tbsp oil into the empty pan.Reduce the heat to medium and slide in the onion, courgette, chard stalks, garlic and 1 tsp ground cumin. Sprinkle in a pinch of harissa (harissa is hot, so use less for a milder flavour). Cook for 5 mins, stirring every so often, till starting to soften.
Tip the chopped tomatoes and cinnamon stick into the pan and return the cooked aubergines. Bring to the boil, then pour in the bulgar wheat and top up with 800ml boiling water. Stir in the chard leaves. Reduce to a simmer, cover the pan with a lid and cook for 10 mins.
Remove the pan from the heat and allow to steam and finish cooking for a further 5 mins.
Fluff up the bulgar wheat with a fork. Grate in the lemon zest and squeeze in half of the juice. Have a taste and add more salt and pepper if you think it needs it. Spoon into bowls and serve with the remaining lemon sliced into wedges.