Blend 6 cloves of garlic, 2 small green chilies, 2 small red chilies, 1 large yellow onion, and 2 inches of fresh ginger in a food processor until smooth
Place a large skillet over medium heat and 4 tablespoons of butter
Once the butter has melted, add the blended chili mixture and cook for about 10 minutes stirring occasionally until the mixture reduces and deepens in color
Add 3 tablespoons of tomato paste, 2 tablespoons of garam masala, 1 tablespoon of ground coriander, 1 tablespoon of ground cumin, 1 tablespoon of turmeric and 1 teaspoon of kashmiri chili powder and cook until the mixture has thickened and deepened in color
Whisk in a cup of chicken stock and work up any brown bits from the bottom of the skillet
Add 29 ounces of tomato puree and a tablespoon of dried fenugreek leaves, cover and simmer for about an hour, stirring occasionally