Combine Greek yogurt, lemon juice, turmeric, garam masala, and cumin in a large bowl and mix together.
Add chicken thighs to the bowl and toss to coat.
Cover, and place in the refrigerator to marinate for a few hours, or overnight.
In a large pot heat butter and oil and add onions, sauteing till golden brown. Stir frequently.
Add garlic, ginger, and cumin seeds, cook for a few minutes longer, until fragrant.
Add tomatoes, cinnamon stick, and jalapeno and cook till jalapeno softens. ~10 minutes
Add chicken and marinade to the pot, let cook for 5 minutes.
Add stock, bring to a boil then reduce to a simmer and cook uncovered for 30 minutes.
Stir in milk and tomato paste and simmer for an additional 15 minutes.
Add almonds, cook for additional five minutes then remove from heat.
Taste for salt, adding salt as needed.
Garnish with cilantro leaves and serve.