4 medium zucchini
   Stuffing:
 1/4 c. red lentils
 1/2 c. bulgur
 3 T. olive oil
 1 onion, chopped
 1/2 tomato, minced
 1 clove garlic, mashed
 1 tsp. salt
 4 tsp. lemon juice
 1/4 c. fresh parsley
   Sauce:   
 2 tsp. cornstarch
 2-1/2 c. plain yogurt
 1 clove garlic, mashed
 salt, pepper to taste
 
 Wash zucchini well.  Do not trim ends. Cut each zucchini in 
 half lengthwise.  Scoop out all seeded portion of zucchini 
 flesh. Sprinkle a tiny amount of salt into each shell. Set 
 aside for an hour.  Wash and drain lentils.  Simmer them in 
 2 c. water for 2 minutes, then let sit, covered, for 45 minutes.  
 In a bowl, cover bulgur with 3 c. water and let sit for an hour.  
 When lentils have sat for 45 min, bring to simmer again. Lower 
 heat and simmer for ~10 minutes or until tender.  Drain and put 
 in a bowl.  Drain bulgur and squeeze out as much liquid as possible.  
 Put bulgur in same bowl as lentils.  Heat olive oil in skillet over 
 medium flame.  Saute onion for 2 minutes.  Add tomato, saute for 
 another 2 minutes. Mix saute with lentils and bulgur.  Add garlic, 
 salt, lemon juice and parsley, mix well.  Arrange a steamer by 
 setting a colander on top of a large pot with an inch or so of 
 water.  Stuff zucchini with lentil-bulgur mixture.  Place stuffed 
 zucchini in colander and cover.  Steam for 10-15 minutes until 
 zucchini shells are just tender.  Sauce:  Mix cornstarch and 1 T. 
 water in a bowl.  Add the yogurt.  Whisk until creamy.  Put yogurt 
 in heavy saucepan and bring to simmer over medium-low heat, 
 stirring constantly.  When yogurt begins to bubble, lower heat 
 and cook for 5 minutes, stirring gently.  Add remaining sauce 
 ingredients and mix.  Put cooked stuffed zucchini on plates 
 and top with sauce.
 
 Source: “Madhur Jaffrey’s World of the East Vegetarian Cooking”