Mix in the cheese (or cheesespread), butter, egg yolk & enough milk to get a soft yet stiff consistency - not watery and add salt to taste.
(Alternatively, you just get the instant mashed potato pack from the stores - boil 2 cups water with 1.3 tbsp butter, then take off heat, add the powdered mashed potatoes & finally fold in 3/4 cup milk evenly till stiff yet soft.
Preheat the oven to 250deg.
Meanwhile, in a saucepan, heat oil, fry onions, green chillies, garlic-ginger paste, cumin pwd, pepper pwd, optional thyme/oregano/rosemary.
Add the cube of chicken stock & then the minced meat and stir-fry till the meat is almost done.
Add the soy sauce or Worcester sauce, tomato paste/pasta sauce & vinegar.
Fry well & then add the frozen vegs (optional).
Cook open till its done and dry it up well (DRY!!!)
Flatten the mince onto your baking dish, then flatten the mashed potato onto it gently with the moist (water) back of a flat ladle,
Take a fork and lightly run lines or concentric circles/squares on it for design.
Place in mid-level of oven for 25 mins and then set on top wrack on 'low-broil' for 2-3 mins to see the lines get darker.
(You may even lightly brush an egg-white over the mashed potatoes before forking the designs over it, for a darker design).