Smita Chandra's Rasam (Spicy Tamarind Soup)

Ingredients

• 2 tbsp. toor dal (yellow pigeon peas), rinsed, soaked 30 minutes, and drained
• 1⁄2 tsp. ground turmeric
• 6 plum tomatoes, chopped
• Kosher salt, to taste
• 2 tsp. rasam powder
• 2 tsp. tamarind paste
• 1 tsp. ground black pepper
• 1 tsp. ground coriander
• 1 tsp. ground cumin
• 1⁄2 tsp. red chile powder, such as cayenne
• 2 tbsp. canola oil
• 1⁄4 tsp. black mustard seeds
• 1⁄4 tsp. cumin seeds
• 1⁄4 tsp. fenugreek seeds
• 15 fresh or frozen curry leaves
• 2 chiles de árbol, stemmed
• 2 cloves garlic, minced