Nothing beats homemade condiments and sauces. Even though it is quite tempting to buy store bought sauces because of their convenience, I think if you have time it is much better to make them from scratch at home. Homemade sauces have no preservatives and are much healthier than the ones in the bottle.
The schezwan sauce is made with red chilies along with the regular Indo-Chinese ingredients like ginger, garlic, soy sauce etc. Recipe is adapted from Veg Recipes of India. It is spicy, tangy and sweet at the same time. The sauce can also be used to make schezwan noodles or even used to dip momos or dumplings.