Sugar is to enhance the flavour. In the same way we add pinch salt to cake. Infact many Asian cuisines does this like in Thai curry.
Again don't trust me I have limited knowledge in cooking.π
No ...i understand. I do add a quarter or half tsp sugar in white pasta or rajma or paneer. Even in mint chutney it tastes good but only if added in very minute amount. But then it's a matter of personal taste as well.

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