Heat a drizzle of oil in a saucepan on a medium-high heat. Add the aubergines and fry for 8–10 minutes. Remove the aubergines from the pan, add the onion and an extra drizzle of oil, if necessary, and fry for 5 minutes.
Add the garlic, cinnamon, and rosemary and fry for 1 minute. Stir in the rose harissa paste, lentils, chopped tomatoes, and generous pinches of salt and pepper. Put the aubergines back into the pan, bring the mixture to the boil, then reduce the heat and simmer for 10 minutes.
Meanwhile, put the butter beans into a separate small saucepan on a medium heat. Add a drizzle of oil, pinches of salt and pepper, and the juice of the lemon. Heat the beans and mash with a masher until smooth.
Serve the aubergine and lentil mixture over the butter bean mash and finish with a drizzle of oil and the parsley.