Place carrots in a large saucepan and cover with water by 3cm. Add the brown sugar and a generous pinch of salt, then set over a medium-high heat and bring to a boil. Cook, stirring occasionally, until all the water has evaporated and the carrots are tender. Reduce the heat slightly and continue to cook for a further 5-10 minutes, or until the carrots start to caramelise. Remove from the heat and allow to cool.
Meanwhile, toast the cumin and coriander seeds in a dry frying pan over a low-medium heat until golden. Allow to cool slightly, then crush into a powder with a pestle and mortar.
Combine the carrots, crushed cumin and coriander, garlic, ginger, cannellini beans, olives, harissa, a glug of olive oil and a good pinch of salt & black pepper in a food processor. Blitz until smooth and silky (if you prefer a little texture that's fine, just blend a little less). Taste and adjust the seasoning, if needed.
Serve the dip topped with extra olive oil, harissa paste, fresh parsley and a good crack of black pepper. Eat with lots of crusty bread.
