Boil the potatoes. Peel the skin and cut into medium cubes. Heat 1 tbsp oil in a pan. Add potatoes, salt and fry until golden brown. Set aside.
Boil water in a saucepan. Add 1/2 tsp sugar, washed spinach leaves and blanch for 2 minute. Remove, wash in cold water and drain.
Grind the spinach with green chillies to a smooth paste. Set aside.
Puree the tomatoes and set aside.
Heat butter in a pan and add the ingredients for tempering. When nice aroma comes, add onion and fry until edges turn brown.
Add ginger, garlic and fry for 2-3 minutes. Then add the tomato puree and cook for 8-10 minutes.
Then add turmeric powder, coriander powder, red chilly powder, garam masala and saute for 2-3 minutes. Sprinkle little water if masala is sticking to the pan.
Now add the spinach puree, salt and 1/2 cup water. Cook for 3-4 minutes and then add the fried potatoes.
Let the potatoes simmer in the gravy for 4-5 minutes. Then add milk, cream, sugar and kasuri methi. Cook for 1-2 minutes and remove from heat.