Sauté the aromatics: Heat the oil in a large skillet or Dutch oven over medium heat. Add the diced onion and cook for about 5 minutes until soft and starting to turn golden. Add the garlic and ginger, cooking for another minute until fragrant.

Bloom the spices: Add curry powder, cumin, turmeric, and cayenne to the pan. Stir everything together and let it cook for 30 seconds to 1 minute until the spices become very fragrant.

Brown the chicken: Push the aromatics to the side and add the chicken pieces. Let them brown for 3-4 minutes, stirring occasionally. They don't need to be cooked through yet.

Build the sauce: Stir in the tomato paste, then pour in the coconut milk and chicken broth. Add the salt and give everything a good stir, scraping up any browned bits from the bottom of the pan. Bring to a simmer, then reduce heat to low.

Simmer: Let the curry simmer uncovered for 15-20 minutes, stirring occasionally, until the sauce thickens and the chicken is cooked through. If it gets too thick, add a splash more broth.

Finish and serve: Remove from heat and stir in the lime juice. Taste and adjust seasoning as needed. Garnish with fresh cilantro and serve over rice or with warm naan bread.