Curry Leaf Popcorn Chicken

Ingredients

• Seeds from 4 green cardamom pods (about ¼ tsp. seeds)
• 2 tsp. coriander seeds
• 2 tsp. cumin seeds
• ¼ tsp. whole black peppercorns
• 2 cups buttermilk
• ¼ cup fresh lime juice
• 2–3 serrano chiles, coarsely chopped
• 6 scallions, roots removed, coarsely chopped
• 1 1" piece fresh ginger, peeled, chopped
• 4 garlic cloves
• 25 curry leaves, preferably fresh, divided
• 1 Tbsp. plus 1 tsp. kosher salt
• 1½ tsp. cayenne pepper, divided
• 2 lb. skinless, boneless chicken breasts, patted dry, cut into 1" pieces
• 2 cups all-purpose flour
• 1 tsp. baking powder
• ½ tsp. baking soda
• Neutral oil (for frying; about 4–6 cups)
• 4 green Thai chiles, seeded if desired
• A spice mill or mortar and pestle

Steps

1. Heat a dry small skillet over medium-high. Toast cardamom seeds, coriander, cumin, and peppercorns, tossing often, until fragrant, about 1 minute. Transfer half of the spices to a spice mill or mortar and pestle and grind to a fine powder; set aside.
2. Blend remaining whole spices, buttermilk, lime juice, serrano chiles, scallions, ginger, garlic, 15 curry leaves, 1 Tbsp. salt, and 1 tsp. cayenne in a blender until smooth. Transfer to a large resealable plastic bag. Add chicken, seal bag, and turn chicken to coat. Chill at least 4 hours and up to 8.
3. Combine reserved ground spice mixture, flour, baking powder, baking soda, and remaining 1 tsp. salt and ½ tsp. cayenne in another large resealable bag. Finely chop remaining 10 curry leaves and add to bag. Shake vigorously to combine.
4. Pour oil into a large heavy pot fitted with a deep-fry thermometer to a depth of 1½". Heat over medium-high until thermometer registers 350°.
5. Meanwhile, remove one-third of the chicken from marinade, letting excess drip back into bag, and transfer to bag with flour mixture. Shake vigorously to evenly coat, then transfer chicken to a wire rack set inside a rimmed baking sheet. Repeat with remaining chicken.
6. Working in batches, fry chicken, turning often and adjusting heat to maintain oil temperature, until golden brown and cooked through, 6-8 minutes. Using a spider or slotted spoon, transfer to a wire rack set over paper towels to drain.
7. Cut Thai chiles in half lengthwise. Add to hot oil along and fry until crispy, about 30 seconds. Drain on paper towels.
8. Arrange chicken on a platter. Top with fried chiles.