Add a splash of oil in a skillet and set to medium-high heat.
Add peppercorns, cumin, mustard seeds, cardamom pods, cinnamon, cloves, coriander, and chilies to the pan. Roast for about 3 minutes or until slightly browned, stirring often.
Remove the skillet from heat and add roasted spices to the blender with tamarind paste, white vinegar, garlic, ginger, and ½ cup of water. Blend until smooth.
Once it’s smooth, your vindaloo masala paste is done.