Here is a recipe for tamarind rasam, a spicy and sour soup that is popular in South Indian cuisine:

Ingredients:

1 cup tamarind pulp
1 tablespoon oil
1 teaspoon mustard seeds
1 teaspoon cumin seeds
1 teaspoon fennel seeds
1 dried red chili pepper
1 tablespoon grated ginger
5 cloves garlic, minced
2 green chilies, minced
1 cup water
1 teaspoon salt
1 teaspoon sugar
1/4 teaspoon ground black pepper
1/4 teaspoon ground cumin
1/4 teaspoon ground coriander
1/4 teaspoon ground turmeric
2 tablespoons chopped fresh cilantro
Instructions:

Soak the tamarind pulp in 1 cup of hot water for 30 minutes.
Strain the tamarind through a sieve, pressing on the solids to extract as much liquid as possible. Discard the solids.
Heat the oil in a large saucepan over medium heat. Add the mustard seeds, cumin seeds, fennel seeds, and dried red chili pepper, and cook until the seeds start to pop.
Add the ginger, garlic, and green chilies, and cook for another minute.
Add the tamarind liquid, water, salt, sugar, black pepper, cumin, coriander, and turmeric to the saucepan, and bring to a boil. Reduce the heat to low and simmer for 10 minutes.
Stir in the chopped cilantro and serve hot.
I hope you enjoy this recipe! Let me know if you have any questions or need any substitutions.