Peel and finely chop the onion. Trim, peel and finely chop the carrot.
Warm a medium pan over a medium heat for 1 min, then add 1 tsp oil, the onion and carrot. Cook for 5 mins till the onion is just soft, stirring every now and then.
While the veg fry, peel and grate or crush the garlic. Peel the ginger and finely grate it. Add the garlic, ginger, 2 tsp garam masala and 1 tsp turmeric to the pan. Season with salt and pepper. Cook and stir for 1 min.
Pour in the chopped tomatoes. Half fill the tin with cold water (around 200ml). Add this to the pan. Stir and bring to a simmer. Drain and rinse the chickpeas, then add them to the pan. Cover and cook for 10-15 mins, stirring now and then, till slightly thickened and the chickpeas are tender.
While the chickpeas cooks, scrub the sweet potatoes and slice them into rounds approximately ½cm thick. Pop in a bowl and toss with 2 tsp olive oil and a pinch of salt.
Put a griddle or frying pan on a high heat for 2 mins, then add the sweet potato slices. Griddle for 2-3 mins on each side till charred. You may have to do this in batches. If you do, pop the cooked potato slices on a warm plate and loosely cover with foil while you cook the rest.
While the potato slices cook, finely chop the coriander stalks. Stir the coriander stalks and baby leaf spinach into the chickpeas to wilt the spinach. Taste the chickpeas and season with a little more salt and pepper if you think it needs it.
Ladle the curried chickpeas into 2 warm bowls and top with the griddled sweet potatoes. Garnish with the coriander leaves and serve.