Par boil the potatoes and then peel them and cut into quarters. Peel the boiled eggs.
Place the eggs and the potatoes in a mixing bowl and sprinkle some salt, 1/2tsp turmeric powder and 1/2 tsp kashmiri red chili powder and toss them in the spices.
Finely slice the onions and chop the tomatoes and keep aside.
In a kadai or a frying pan, take 2 tbsp of mustard oil. When the oil is hot, add the eggs and fry them on a medium heat till the skin has turned golden reddish and brown in colour. Take the eggs out and keep aside.
In the same oil, lightly fry the potatoes till they have a golden colour. Then take the potatoes out of the kadai with a slotted spoon and keep aside.
Add 2 more tbap of oil in the same kadai and let it heat. Add dried bayleaf, cinnamon, cloves and cardamom to the hot oil. Also add a couple of split green chillies.
When the spices have got some colour, add the sliced onions and stir. Crush the garlic pods with the flat end of your knife and add to the onions.
Now over high heat to medium heat, fry the onions till there is a golden colour.
Add the ginger paste and stir for a couple of minutes and then add the chopped tomatoes.
Add the rest of the turmeric powder, Kashmiri red chilli powder, cumin powder, little bit of salt and the sugar and give it a good stir. Fry until the tomatoes have become soft and the spices have cooked.
If the spices are sticking to the sides, sprinkle some water. Add the potatoes and fry the potaoes further with the masala. Add the ketchup at this point. sprinle some water and cover and cook till the potatoes have become soft.
At this point, add the eggs and combine everything. Add more salt if required and split the green chillies and add them to the gravy.
Add 1/3 cup warm water and combine. Now increase the heat and give the gravy a boil till oil starts coming out from the sides. Drizzle a tbsp of mustard oil and cook it for a few second and then turn off the heat.
Dim kosha is ready and can be served with luchi or roti/ pualo or fried rice.