For roll, make a dough of wheat,semolina,salt & required water.Cover it & keep aside.
For manchurian, boil cauliflower cubes with water & a pinch of salt.
Make a thick batter of gram flour, corn flour, turmeric powder,salt & red chilli powder.
Now dip the boiled cauliflower pieces in it & deep fry it.
For gravy, heat 1tspn oil, add choppedonion, ginger garlic.Saute it for a while.
Add chopped capsicum, tomato & spring onion.
Add all sauces, salt & pepper powder.Cook it for 5 to 7 mins.
Now mix 2tspn corn flour with 5tspn water & mix it to gravy.
After few minutes, add fried gobi.Add extra tomato chilli sauce.Toss it for 3 to 4 mins & switch off the flame.
Now for chapati, take a ball from wheat dough, roll it & make chapati using oil or ghee.
Take a plate now.Place the chapati on it,spread tomato chilli sauce in the middle portion of the chapati.Put 3 to4 gobi manchurian pieces with some dry gravy.Add chopped cucumber,onion & chat masala.
Wrap it with foil or tissue paper & serve it.If u like extra spice, add chopped green chilli.