Here is how I would do. More focus is on method and not on the quantity ratio.
1. Peel potatoes and carrot, wash them under running water and then dry them by patting with cloth or tissue. Cut them into small cube shaped pieces. (Tip : making them dry will avoid sticking to vessel while cooking).
2. Put washed (and dried) 'batta' on stove (gas-burner / heating-coil / induction or whatever). Heat the batta on medium flame for a minute. (Tip : doing this will avoid cooking oil getting smoked up).
3. Put oil (refined / mustard / sunflower or whatever oil you use) in 'batta' and heat on medium flame till the fumes start rising slowly.
4. Lower the flame. Now add zira (cumin) to oil. Wait till the bubbles of zira goes away.
5. Then put carrots to it slowly and mix it well with oil. Cook it on medium flame for some time with 'batta' covered with plate. Occasionally stir it one or two times.
6. Once you start seeing the carrots are getting little soft. Then add potatoes to it and mix it well with carrot. Again cover the 'batta' with plate and let it cook on low flame. Occasionally keep stirring it one or two times so that it does not stick to ‘batta’.
7. On seeing both potato and carrot getting real soft then add coriander (dhaniya) power and turmeric (haldi) power. Mix well and let it cook on low flame. Do not cover this time. Keep stirring to avoid sticking of sabzi to 'batta'.
8. In next few minutes add Salt, mix it well and let it cook on low flame with 'batta' covered for a minute or two. You are done and good to go.
This is simple and real quick. All it takes in 20 minutes and far less number of ingredients.
If you want it more fancy one then I may re-write it at what point to add onions, garlic, ginger, tomatoes, cilantro, asofetida and what not.
Bhul Chuk Maaf.
Waheguru Ji Ka Khalsa,
Waheguru Ji Ki Fateh.