In the same pan, add the tomatoes, minced garlic, fresh ginger, turmeric, cayenne, garlic powder, paprika, cumin, salt and 1 teaspoon of garam masala. Bring the mixture to a simmer, and cook for 10 minutes, stirring often. Use an immersion blender (or a food processor OR a regular blender), and blend the tomato spice mixture into a smooth sauce.