Here is a recipe for a Tamarind Chutney with Bananas and Raisins, it's called Imli Ki Meethi Chutney and is a family recipe of Madhur Jaffery.

Break up the tamarind into small pieces and soak them overnight in 2/3 cup hot water in a small nonmetallic bowl or cup so pieces are covered. The next morning, mash the soaked tamarind in the water, making a thick, uneven pulp using your hands or the back of a wooden spoon. Place a strainer over a nonmetallic, or stainless steel bowl. Put the tamarind pulp in the strainer, and press down with the back of a wooden spoon. Keep pressing until nothing but fibrous tissues and seeds are left in the strainer. Put the fibrous tissues and seeds in a clean bowl and add another 2 tablespoons of hot water. Mash some more. Put back in the strainer and strain some more. Discard the strained pulp on the outside of the strainer - it doesn't always drip down. (This is the basic tamarind paste and may be frozen.) Mix the strained pulp with the sugar, salt, cumin, and cayenne, tasting as you go to get a perfect balance of flavors. (This is the basic tamarind chutney and may be frozen.) A couple of tablespoons of this chutney can be spooned over yogurt relishes for an added sweet and sour taste.) Drain the raisins and add them to the chutney. Just before eating, cut the banana into 1/4 - 1/3 inch thick slices and mix with the tamarind pulp.

>From Madhur Jaffrey's Spice Kitchen.