Add the tomato passata, garlic, ginger, garam masala, turmeric, paprika coriander, salt, almonds, yogurt to your food processor and process on high until smooth.
Toss the chicken with the paste and mix well. Cover with a plastic wrap and refrigerate for 1 to 2 hours.
Add the olive oil and butter to a large skillet over medium high heat. Add the onions and cook for 5 minutes or until they start to brown a bit and are softened.
Add the chicken to the skillet, including the yogurt mixture that's left in the bowl and cook for about 15 minutes or until the chicken is cooked through.
Stir in the heavy cream and mix well. Cook for an additional 5 minutes.
Garnish with yogurt and cilantro, if preferred. Serve over rice and naan bread.