For the Marinade

175 g full‑fat Greek yogurt

1 Tbsp garam masala

1 Tbsp ground cumin

1 Tbsp ground coriander

¼ tsp mild or medium curry powder

2 tsp turmeric, divided

1 tsp chili powder

1 tsp chili flakes

Zest of 1 lemon

1 kg boneless, skinless chicken thighs, halved

Salt and pepper to taste

For the Base & Sauce

1 medium yellow onion, chopped

1 shallot, finely chopped

6 garlic cloves, minced

2-inch piece fresh ginger, minced

1 Tbsp olive oil (plus more if needed)

4 Tbsp tomato paste

400 ml full‑fat coconut milk