First, take the fenugreek leaves and wash them in clear water twice or thrice so that the soil or mud that presents in the stem clears properly.
Then take each stem pluck all the leaves which present in the stem and after plucking the leaves throughout the remaining stem.
Then finely chop the fenugreek leaves and keep them aside. I use 3 cups of chopped fenugreek leaves.
After that take 3 medium-sized potatoes peel them and chopped into square and medium-thin slices not very thin. Wash it twice in clear water and keep it aside.
Take a pan or a kadai which you have on a stovetop on medium heat and add 1 tbsp mustard oil with 1 tsp cumin seeds and sizzle them for a few seconds.
After that add chopped onion and saute them for 2 minutes or until they have a little golden texture outside.
Then add chopped potatoes with 2 tbsp of water and cook them for 10 minutes on low heat with covering the pan or kadai. Stir at intervals.
After ten minutes when the potatoes are almost soggy but there is some stock of water.
Now add chopped fenugreek leaves. Mix well.
Then add chopped green chili, 1/4 tsp turmeric powder, and salt to taste.
Mix all of these ingredients well and cook on low heat for about 8 to10 minutes until the sabji absorbs water properly. Sir at intervals so that the potatoes and fenugreek leaves do not stick at the bottom of kadai.
After 10 minutes you see the the sabji absorbs all water properly and the sabji looks dry. There is no water in final preparation. Then turn off the heat. Now you can serve it.