In a medium-large dish add yogurt, Garam Masala, Cumin, Salt and Turmeric. Stir to incorporate.
Cut chicken breasts and thighs into 3 pieces. Add to the yogurt mixture and toss well so the chicken can marinate for 30 minutes.
Prepare onions, jalapeno and grate ginger, individually and set aside.
Heat Ghee (or clarified butter) in a Dutch Oven along with vegetable oil.
Add Cumin seeds and sauté for 2 – 3 minutes.
Next add the onions and slowly sauté for 10 minutes before adding the jalapenos. Saute another 5 minutes.
Add the grated ginger and garlic, stir and cook for 2 minutes.
Add tomato sauce, stir for about 1 minute and add Passata. Stir and bring to a boil.
Add chicken and all yogurt/spice mixture. Cover, return to a boil, and reduce heat.
Let curry simmer 25 minutes until chicken is cooked through.
Garnish with plain yogurt and cilantro if desired.