Fresh ginger, jalapeno, and red-pepper flakes give this bold tomato sauce just the right amount of heat. It's a key component of Martha's Beef Biryani.
Heat oil in a medium saute pan over medium. Add onions, garlic, ginger, and jalapeno; season with salt and pepper. Cook, stirring occasionally, until softened, about 5 minutes. Add tomatoes, cilantro, cardamom, cumin, red-pepper flakes, spice blend, tomato paste, and 1/2 cup water.
Transfer to a food processor and process until mixture is smooth. Transfer to a medium saucepan. Let simmer on low heat until thickened, about 10 minutes.