In a bowl, add 1/4 cup of hot water. Add dates and chopped jaggery and set aside for 1 hour. If you soak them into normal water then it will take 4-5 hours to soften.
Take another bowl, soak tamarind in 1 cup of hot water. Set aside for 1 hour. You can soak tamarind in normal water for 4-5 hours or overnight as well.
Squeeze out the pulp from the tamarind and set aside.
In a grinding jar, add tamarind pulp, soaked dates, and jaggery and blend them into a smooth paste.
In a strainer, add the tamarind and dates paste and strain it into a bowl.
In a pan, add tamarind paste, ginger powder, coriander powder, cumin powder, red chili powder, sugar, and salt. Add 2-3 tbsp water and mix well.
On medium to low heat, let the sauce cook by stirring it continuously till it becomes thick and shiny - for about 12-15 minutes.
Once it cools down completely, store it in an airtight container in the refrigerator.