Method for the caramelised onions: Heat a non-stick pan. Add oil and butter. When the butter melts, add the onions and sauté till these are soft, about 10 minutes. Now add the brown sugar and sauté for 2 min. Add the Balsamic vinegar and cook on a slow flame for 35 min, till the onions are caramelised and turn soft and sticky. Cool down to room temperature.
Method for the Tangy Posto Sauce: Mix the poppy seed paste (ground finely with some water), Soul Chundo, ginger paste, green chilli and salt in a blender. The sauce should be smooth and should taste tangy.
Method for the balls: In a deep mixing bowl, mash the paneer and boiled potato well, so that you get a smooth dough. Add four very finely chopped mint leaves. Reserve the rest of the mint leaves for garnishing. Also add the toasted peanuts (ground coarsely), Soul green chilli pickle and Soul garlic pickle to the paneer dough and mix well. Adjust the seasoning, if necessary.
Make small balls out of this dough. Flatten each and stuff with little caramelised onions. Reshape each into a ball and refrigerate for 10 min.
After 10 min, take out the balls from the refrigerator and coat them with beaten egg. Roll them in breadcrumbs.
Deep-fry in medium heat until these turn golden-brown. Drain on an absorbent paper. Garnish with raw mango slices and mint leaves and serve with the Tangy posto sauce.