Paruppu usili can be made with
Green bell peppers, Green Beans, Guvar (Kothavarangai) Plaintain flower. (Vazhai poo) Cabbage
The recipe preparation might seem lengthy, but its worth the time. I steamed the usili in my MW cooker and this is how I prepared it. Microwave Idli Cooker: I have this microwave idli cooker and it took me 4.5 mts for the steaming process. I usually add 3 to 4 tbsps of water and microwave it high for 3 minutes. Then grease the trays and keep idlys or this usili mixture and steam accordingly.
Ingredients:
Any of the above mentioned veggie (I am taking beans) – ¼ lb Channa dhal (kadalai Paruppu) ¼ cup Toor Dhal ¼ cup Dry red chillies 3 to 4 Salt – ¾ tsp for beans and ¾ tsp for usili Hing Asfotedia – ½ tsp Mustard seeds 1tsp Oil – 1 tbsp Water – ¼ cup
Steps:
Usili Preparation Soak Channa dhal, toor dhal and the red chillies for at-least 30 mts. Grind the soaked dhal mixture with hing, turmeric and salt by adding very little water. (Not more than 2 tbsps) Don’t make it too smooth. Coarse grinding is fine. Then make balls out the grinded mixture, using idly trays to steam them. If you have microwave rice cooker, it takes 4.5 minutes for boiling. Once it is done let it cool and crumble the dhal balls into coarse mixture. Preparing the curry: Chop the green beans and boil it. Either you can steam it in microwave or when you are preparing the usili you can do it in stove top also. As it takes only 5-6 minutes I go with stove top. Heat the kadai and add oil. Once the oil is heated add the mustard seeds. As it starts to splutter, add the beans and salt. Sprinkle some water and cover and cook for unto 5 mts. Then remove the lid and cook it all the water evaporates. Now add the crumbled dhal mixture or the usili and mix well. Mix well and let it cook for 3 minutes and thats it yummy usili is ready. 
