Scrub the sweet potatoes leaving the skin on, cut the ends off and cut into halves lengthwise. Place the sweet potatoes on a baking tray and roast for approx. 1 hour. Remove the sweet potatoes from the oven and allow to cool for 5-10 minutes.
For the dahl: Peel and finely chop the garlic, ginger and scallions. Drain the chickpeas and lentils and rinse thoroughly. Chop the cherry tomatoes in half.
Heat 1 tablespoon of oil in a large saucepan on a high heat. Add the garlic, ginger and the scallions and reduce the heat to medium, cooking for 1 minute. Add the cherry tomatoes and cook for a further 2 minutes.
Add all the remaining ingredients, bring to the boil, stirring occasionally to make sure it does not stick to the bottom. Reduce heat to simmer for 3-5 minutes.
Scoop out the flesh from the sweet potato and place into a large mixing bowl. Place the empty skins back onto the tray and bake for 10 minutes to get crispy.
While the skins are baking, mash up the sweet potato flesh. Now mix half the dahl with the sweet potatoes and mash together.
Fill each crispy skin with the sweet potato curry mixture. Pop back into the oven for 5 minutes to heat through. Serve with the remaining dahl poured over the stuffed potato skins and garnish with some chilli flakes, fresh coriander and dairy free yogurt of choice.