Add olive oil to a large skillet over medium heat. Add onions and sauté for 3-5 minutes until onions are soft. Add garlic and ginger and sauté for one minute.
Add in butter, chicken stock, tomato paste, cinnamon, salt, cumin, garam masala and turmeric. Stir to combine and bring to a simmer over medium heat.
Stir in chicken and stir until coated. Cover and cook for 15 minutes, until chicken is cooked through.
Stir in lemon juice and heavy cream. Return to a simmer and cook until heated through, about 2 minutes.