Rinse the cilantro and fresh mint leaves thoroughly under cold water and roughly chop them. Chop the green chilies and ginger as well.
In a blender jar, add the chopped cilantro, mint leaves, ginger, and sliced green chilies. Add the ground whole spices - black peppercorns, fennel seeds and seeds of black cardamom to the blender.
Add a few tablespoons of water to the blender and blend the ingredients into a smooth paste.
Place the tamarind pulp in a large bowl or you could use a pitcher as well
Strain the blended green herb paste over the tamarind pulp using a fine mesh sieve or cheesecloth. Press the paste with the back of a spoon to extract as much liquid as possible.Tip - Straining the blended paste contributes to a smoother taste of the panipuri water. If not strained, your pani could be stringy. Dont skip this step. Add chaat masala powder, roasted cumin powder, black salt, hing, and red chili powder. Squeeze the lemon juice and mix in the sugar. Stir with a spoon or whisk until fully dissolved.
Add cold water gradually to the concentrated mixture, stirring continuously, until the desired consistency is reached. The pani should be thin and watery.
Taste the golgappa pani and adjust the salt, chaat spice powders, sugar, and lemon juice as needed. The pani should be tangy, spicy, and slightly sweet.
Refrigerate the pani puri pani for at least an hour before serving.