First blanch the spinach.Boil water in a big vessel and add cleaned spinach and sugar to it. Allow it in hot water for 1 min.Strain the spinach(don't discard the water,can be used in gravy),run under running water and immediately transfer it into ice cold water.Note the green color pop.
Grind diced onion,ginger and garlic. Keep aside.
Grind spinach and green chilli to a fine paste . While grinding add little lemon juice ,this will help in retaining the green color. Open the mixer jar and keep , else the color will change.
Heat oil and butter in a wok / kadai .Add bay leaf ,splutter cumin seeds.Once they crackle add chopped onion and ground onion -ginger-garlic mixture and fry well till raw smell goes.
Once they turn translucent, add dhania powder, jeera powder ,amchoor powder and kasoori methi . Mix well.
Add spinach puree, cooked corn, garam masala and salt.Mix well. If required dilute the gravy by adding strained palak water to get the desired consistency.Cook over medium flame for about 4-5 mins. Don't cover while cooking, else the green color will fade.
Remove it from stove, if req add lemon juice. Mix and serve hot with phulka / roti / naan / jeera rice.
Notes
How to retain the green color of spinach in gravy :
While blanching spinach, add little sugar . This will enhance the color .
After removing the spinach from hot water, immediately transfer it into ice water. Helps a lot in enhancing color
While pureeing spinach add lemon juice .
Don't cover while cooking, else the green color will change.
Dont over boil spinach.
If you want you can add little cream or milk or curd to the gravy to make it more rich and give some texture. However , i like it plain.
If you want u can diced ,roasted paneer too..
I have heard that adding tomato to spinach leads to kidney stones.So i never add tomato to any of my spinach dishes.
Corn can also be substituted with cubes of fresh paneer, baby corn or a combination of garden fresh veggies of your choice.