In a large pan with a lid, heat the oil under medium high heat. Add the red onion and cook until translucent. Add the green onion and ginger and saute for two minutes.
Add the garlic powder, cardamon, paprika, cumin, turmeric, garam masala, cinnamon, cayenne pepper, salt, and pepper. Mix well and cook for one minute.
Add the diced tomatoes in their juices, mix well, bring to a boil, cover and lower the heat to a very low simmer. Stirring every couple of minutes.
While the onions, tomatoes, and spices cook, cook the pasta according to package instructions.
When the pasta is ready, drain it and save one cup of pasta water.
Return the pasta to the pot and add the sauce. Mix well and add more pasta water if needed.
Squeeze half a lemon and add the brown sugar, agave, or maple syrup. Mix well and garnish with sliced green onions and crushed red pepper.
Notes
Bloom the spices: This is an important step to bring out all the flavors in the spices for a more full-bodied tandoori sauce.
Cook pasta al dente: It will continue to cook when combined with the hot tandoori sauce, so this ensures it doesn’t become overcooked and mushy.
Save some pasta water: It helps thin the sauce while the starches help the sauce cling to pasta, making it a great addition to any homemade pasta sauce.
Tweak the flavors: Feel free to adjust the ratio of the spices and/or the amount of lemon and sweetener added to taste.