Heat your oven to 200°C/Fan 180°C/Gas 6. Chop the broccoli into small florets. Thinly slice the stalk.
Peel and grate 1 garlic clove and place in a large bowl. Squeeze in the tahini. Pour in ½ tbsp oil and whisk together.
Tumble in the broccoli and toss to thoroughly coat it. Spread the broccoli out onto a baking tray and slide into the oven. Roast for 15 mins till just softened and caramelised. Toss the broccoli halfway through. Turn the oven off and leave it to stay warm in the oven after 15 mins.
While the broccoli roasts, peel and thinly slice the onion. Peel and thinly slice the remaining garlic clove. Halve the chilli and flick out the seeds. Finely chop it.
Heat a pan for 1 min. Add ½ tbsp olive oil and the onion. Cook for 5 mins till just softened. Add the garlic and chilli and cook for 1 min.
Drain the chickpeas and tip them into the pan with ½ tsp harissa. Add 2 tbsp cold water. Cook on a gentle heat for 5 mins. Take off the heat and use a masher to crush the chickpeas lightly. Taste and season with salt and pepper. Add more harissa to taste, if it needs it – it's spicy!
Zest and juice the lime. Swirl it through the yogurt with a pinch of salt and pepper.
Divide the broccoli between 2 plates. Spoon over the chickpeas. Add a dollop of lime yogurt. Dust over a little harissa to serve, if you like.