Sweet potato-turia-lauki subji

I had sweet potatoes, a few chunks of lauki which were already chopped and which I wanted to finish, and a turia. I just wanted to try this combination, and with some trepidation, set about thinking up of how I wanted it to taste.
Do let me know by comments or email, if you can think of a different and interesting masala to this combo.

Ingredients
Sweet potato skinned and chopped to chunks 1 cup
Lauki skinned chopped to chunks 1 cup
Turia skinned and chopped to chunks 1 cup
Onion 1 big grated
Tomato 1 big grated
Ginger garlic paste 1 tsp
Chilli powder 1 tsp
Coriander powder 1/2 tsp
Cumin powder 1/4 tsp
Turmeric powder 1/4 tsp
Garam masala to taste
Crushed jaggery 2 tsp
Chopped coriander leaves 1 tbsp
Oil 1 tbsp
Salt to taste
Water 1/2 cup

Method

1. Heat oil in a pan or kadai. I used my tiny hawkins.
2. Add the grated onion and stir for few mins. Add the ginger garlic paste and grated tomato and stir for a minute or two.
3. Add the chopped sweet potato, lauki, turia salt and mix well.
4. Add the chilli powder, coriander powder, cumin powder, turmeric powder, garam masala and mix well.
5. Add 1/2 cup water and cook covered for 10 mins or till well cooked. 
6. Adjust salt to taste, add the jaggery and simmer for few mins. 
7. Add chopped coriander leaves and give it a good mix.

Serve hot with rotis or phulkas. It will be a semi-gravy dish.
Sonny baba loved it.  :-)