In a large pot over high heat, add at least 2 quarts of water and 1 tablespoon of kosher salt (or 1 1/2 teaspoons of sea or table salt), and bring to a boil. The salt will ensure your pasta is well flavored.
Meanwhile, In a medium pan over medium heat, add 1 1/2 teaspoons oil. When hot, add the ground meat or poultry (or extra-firm tofu crumbles). Mash the meat into crumbles and stir occasionally for about 7 to 9 minutes or until completely browned. Remove it with a slotted spoon and discard any remaining fat.
Using the same pan, heat the remaining 1 1/2 teaspoons of oil over medium-high heat and add onion and 1 teaspoon of salt. Cook until the onions are begining to brown, about 8 minutes. Reduce heat if necessary to keep the onions from sticking, and/or add a tablespoon of water.
Turn down the heat to medium and add the ginger garlic paste to the onions. Stir for 1 to 2 minutes until the paste no longer smells raw. Add the chili powder, cloves, cinnamon, coriander, and turmeric. Stir, cooking the spices for another minute, then add the tomato.
Cover and simmer for 6 minutes if using the puree or sauce. If using fresh tomatoes, add another 5 minutes to the cooking time, or until the tomatoes are completely broken down.
When the water is boiling add your pasta, give it a good stir. Cook until al dente (while it still has some firmness) or to your preference.
Return the meat or tofu (or add cooked lentils) to the pan with the onions and tomato mixture. Cook for 7 more minutes stirring several times, continuing to break down the meat.
When the pasta is finished cooking, reserve a 1/2 cup of pasta water and add the pasta to the sauce. Cook together over medium heat, adding pasta water as needed so the sauce coats the pasta well. Simmer together for a few minutes so that the pasta is flavored with the sauce, adding cooking water as needed if the sauce is too dry.
Add about 1/4 cup of parmesan cheese for more flavor and richness, if you wish. See Notes below about adding some additional dairy or coconut milk.
Taste for salt and chili pepper, adjusting the seasonings as needed. Garnish as you wish with parmesan cheese or cilantro and serve with flatbread.
For a vegetarian version of Indian spaghetti bolognese, use roughly 14 ounces of extra-firm tofu or a 1 1/2 cups of cooked green or brown lentils (that hold their shape) instead of ground meat or poultry.
Skip the cheese for a vegan twist. If you are eating gluten-free, swap out the regular pasta for a gluten-free flour one or serve over rice.
To up the vegetable quotient, add 1 cup cooked carrots, peas, corn, or mushrooms when you return the meat or tofu to the onion and tomato mixture.
If you find the flavors of this sauce need mellowing out or it needs some added richness, stir in some yogurt, coconut milk, or heavy cream.
If you want to play with other spicing ideas, here is a good place to start: