I got this recipe from Anthony Kitchen and he said that it can be served with Biryani as a side dish.
Cut the 3-4 karela in circular slices, thinner the better.
Cut a large potatoes into semi- circular slices. If the potato is large, cut the slice into another half to give a semi-semi circular( or quarter of a circle).
Cut a large Onion anyway you want to.
Heat oil in a pan. Use oil generously say 4-5 Table spoons, if you are not into oily stuff, you may remove the dish onto a Tissue paper to remove exces oil.
Add a Tsp of whole jeera. Let is crackle, and then add the onions and 2 green chillis sliced in halves.
Add the potatoes and karela, and keep frying. Don’t let it burn and don’t cover. Keep stirring.
When they are almost done, sprinkle some red chill and salt to taste