Step 1

Cut the potatoes into 3/4 inch pieces. Cover with water. Add the salt and turmeric. Bring to a boil. Cook until the potatoes are just tender. Drain and let cool.

Step 2

Heat the oil in a skillet over medium heat. Add the cumin seed, mustard seed and panch phoran. When the whole spices start to crackle add the potatoes. Cook until the potatoes start to turn golden. Remove the potatoes from the pan.

Step 3

Return the pan to the heat. Add enough oil to get to two tablespoons. Stir in the green chili. Cook for about 30 seconds, stirring constantly. Add the garlic ginger paste and cook until it stops spattering. This takes under a minute.

Step 4

Turn the heat down to medium low. Add the Indian restaurant spice mix, kashmiri chili powder, kasoor methi and salt. Stir to combine. Cook for about 30-45 seconds. You want your spices to lose their raw flavour but don't want them to burn. Watch closely. Lift the pan away from the heat if you have to.

Step 5

Add the diluted tomato paste and stir. Turn the heat up to medium high.

Step 6

Add half (6 oz) of the curry base. Cook until it starts to form craters. This takes about 2 minutes. Add the rest of the curry base. Repeat.

Step 7

Turn the heat down to medium low. Add the potatoes, drained spinach and lemon juice. Simmer for 4-5 minutes. Serve.