Preheat the oven to 200 °C (390 °F) circulating heat.
Place sweet potatoes in one/two casserole dishes (or on baking paper) and prick them several times with a sharp knife. Bake the sweet potatoes without any further oil or liquid at 200 °C for 45-50 minutes.
Rinse cooked chickpeas and dry them thoroughly with a kitchen towel. Mix the chickpeas with 2 tbsp olive oil, 1 small tsp cumin, 1 tsp ras el-hanout, a pinch of salt and chilli flakes to your liking.
If you want, mix in 1-2 tsp of Sriracha chilli sauce (optional). Then spread the chickpeas on a sheet of baking paper.
Put marinated chickpeas to the sweet potatoes in the oven. Bake chickpeas together with the potatoes at 350 °F for about 18-20 minutes until well roasted.
Wash tomatoes, core and dice.
Peel the onion and a clove of garlic and finely dice.
Heat oil in a frying pan. Soften the onion and garlic cubes. Then add the tomato pieces and sauté for 2-3 minutes. Drizzle tomatoes with agave syrup and caramelise briefly. Add a little water. Season the tomato cubes with sweet paprika powder, chilli flakes, Provencal herbs and sea salt. Simmer the tomato sauce for 5 minutes and then remove from heat. Puree the sauce with a hand blender or in a blender. If necessary, add a little more water to get the desired consistency and season the sauce with sea salt.
Mix the soy yoghurt with 3 tbsp of lemon juice, a dash of salt and coarsely ground pepper. Wash a handful of fresh mint, shake dry and chop the leaves. Stir in the mint leaves in the yoghurt sauce.
Cut the sweet potatoes in halves. Cut the pulp diamond-shaped and pull apart slightly so that the sauce can infiltrate. Spread the tomato sauce over the potatoes and add the yoghurt sauce. Spread roasted chickpeas over the sweet potato halves and sprinkle with mint. Garnish the dish with black sesame seeds and limes.