Pull the leaves and silks off the corn cobs. Stand the cobs upright. Carefully run a knife down the sides to cut off the kernels. Peel and grate the garlic. Drain the chickpeas and rinse.
Trim the lettuces and cut vertically into quarters. Don’t worry if a few of the outer leaves fall off. Pour 1 tbsp oil into a large frying pan and bring to a medium-high heat. Add the lettuce wedges and a pinch of salt and pepper. Fry for 1-2 mins on each side, till golden and slightly wilted, then transfer to a large bowl. Keep the pan on the heat.
Pour 1 tsp oil into the now empty pan and slide in the corn, drained chickpeas, a pinch of harissa (it’s spicy, so use as much or as little as you like) and the garlic. Sprinkle in a little salt and pepper and stir well to combine. Fry for 5 mins, stirring occasionally, till the corn and chickpeas start to caramelise on the outside. Tip into the large bowl with the lettuce leaves.
Peel and finely chop the onion. Trim the tomatoes and chop into small pieces. Slide into the bowl.
Grate the zest from the lime into a separate small bowl. Squeeze in the juice. Sprinkle in a little salt and pepper, and whisk in 1 tbsp oil to form a dressing. Pour over the salad and toss together till everything is coated. Spoon onto plates and serve.