Heat couple of tablespoon of oil in a saucepan. Once hot, carefully place the tofu cubes and let it brown and crisp. It takes about 8-10 minutes on medium-low heat. Flip and let the other side cook for 5 minutes. Remove with a slotted spoon and transfer to a bowl covered with kitchen tissue. Cook all the tofu bites and set aside.
Heat 1 tablespoon oil in a clean saucepan. Add the onions and sprinkle little salt. Cook covered in medium-low flame for 15 minutes until they brown and caramelize well. Set aside.
Whisk sriracha with mayo. Add more sriracha if you like more spicy. Taste the dip and decide. Set aside.
I served the appetizer as individual servings in ceramic spoons. Place one tofu cube in each spoon, sprinkle chaat masala, little salt —–> top with caramelized onions and sriracha-mayo.