📖 Instructions

1. **Step 1: Marinate the Chicken** In a large bowl, combine the boneless, skinless chicken thighs (cut into 1.5-inch pieces) with plain yogurt, ginger-garlic paste, Kashmiri chili powder, turmeric, cumin, garam masala, and salt. Mix well to ensure every piece is coated. Cover the bowl and refrigerate for at least 2 hours, or ideally, overnight. This is vital for tender, flavorful chicken.
2. **Step 2: Prepare the Sauce Base (Part 1)** Heat 1 tablespoon of ghee or unsalted butter in a large Dutch oven or heavy-bottomed pot over medium heat. Add the chopped red onion and sauté until it becomes translucent and softened, about 6-8 minutes. Don't rush this step, as sweet onions contribute greatly to the sauce's depth.
3. **Step 3: Aromatic Infusion** Stir in the remaining ginger-garlic paste and the whole green chilies (if using, remember to slit them slightly). Cook for another 2-3 minutes until fragrant, being careful not to burn the garlic. The aroma will be intoxicating at this point!
4. **Step 4: Spice it Up!** Add the coriander powder, red chili powder (adjust to your spice preference), and remaining garam masala. Cook for about 1 minute, stirring constantly, until the spices are fragrant. A little trick: if it seems too dry, a splash of water can prevent burning.
5. **Step 5: Tomato & Cashew Foundation** Pour in the crushed tomatoes and the raw cashews. Stir everything together. Bring the mixture to a gentle simmer, then reduce the heat to low, cover, and cook for 15-20 minutes, allowing the tomatoes to break down and the cashews to soften. Stir occasionally to prevent sticking.
6. **Step 6: Blend for Smoothness** Carefully transfer the sauce mixture to a heat-safe blender or use an immersion blender directly in the pot. Blend until the sauce is completely smooth and creamy. If you're using a regular blender, remember to vent the lid for steam and blend in batches. Strain the sauce back into the pot using a fine-mesh sieve for an extra silky texture, pressing down on any solids.
7. **Step 7: Sear the Chicken** While the sauce simmers, heat another tablespoon of ghee or butter in a separate large skillet over medium-high heat. Remove the marinated chicken from the fridge. Working in batches if necessary (don't overcrowd the pan!), sear the chicken pieces for 2-3 minutes per side, just until they develop a nice golden-brown crust. They don't need to be cooked through; we're just building flavor and color.
8. **Step 8: The Slow Simmer Begins** Add the seared chicken pieces directly into the pot with the smooth tomato-cashew sauce. Stir gently to coat all the chicken. Reduce the heat to low, cover the pot, and let it simmer for at least 45-60 minutes. The longer and slower, the more tender the chicken becomes and the more the flavors deepen. Stir every 15 minutes or so to ensure even cooking and prevent sticking.
9. **Step 9: The Buttery Finish** After the long simmer, stir in the unsalted butter, heavy cream, and dried fenugreek leaves (kasuri methi). The fenugreek leaves should be gently crushed between your palms before adding to release their aromatic oils. Continue to simmer for another 10-15 minutes, uncovered, allowing the sauce to thicken slightly and the cream and butter to fully incorporate.
10. **Step 10: Final Touches and Taste** Taste the butter chicken and adjust seasoning if needed. You might want a pinch more salt, a touch of sugar for balance, or a bit more red chili powder for an extra kick. If the sauce is too thick, a splash of warm water or chicken broth can thin it out. Garnish generously with fresh cilantro.
11. **Step 11: Serve with Love** Ladle the hot butter chicken into serving bowls. It’s absolutely heavenly served with warm naan bread, fluffy basmati rice, or even a side of crisp cucumber raita. Enjoy this labor of love!