1. Boil potatoes in a pot until they are tender and mash them until no lumps remain. Add the all ingredients "A" and mix well. Set aside.
2. In a cooking pot, fry garlic until fragrant and add vegetables (B), onion, carrot, celery. Fry the vegetable until they become wilted. Add ground lamb and continue stir frying until no longer pink.
3. Add tomato from a chopped tomato can and the ingredients "C". Bring it to a boil over medium high heat. Reduce the heat to low. Uncover and simmer for about 40 mins. Transfer the meat sauce into a baking dish (casserole) and sprinkle grated cheese over the sauce. Spoon the mashed potato over the meat filling.
4. Pre-heat the oven to 190C degree.
5. Bake for about 30 minutes or until lightly browned.