For the carrots, place all of the carrot ingredients into a small pan with a tight fitting lid and bring to a gentle simmer. Cook with the lid on for 6-8 minutes, or until the carrots are tender.
For the lamb, heat the olive oil in an ovenproof frying pan and sear the cutlets on both sides for one minute. Mash together the remaining lamb ingredients in a bowl and spread onto the seared cutlets, then transfer to the oven to cook for 5-7 minutes, or until the crust is golden-brown.
For the onion marmalade, melt the butter in a small pan and gently fry the onion with the sugar for 3-4 minutes, or until softened. Add the balsamic vinegar and cook for 4-5 minutes, or until the mixture is thick and sticky.
To serve, spoon the onion marmalade onto a serving plate and place the lamb on top. Serve the carrots alongside.