Slice onions thin. Sprinkle salt and cornstarch. Toss together. Fry the onions in oil heated to 350°F for 10-12 minutes and drain on a paper towel.
Saute garlic until fragrant. Add onions, tomato sauce, tomato paste, water, salt and pepper. Bring to a boil, reduce heat and cover, let simmer for 15 minutes.
Cook lentils until they are al dente. Stir in rice, vermicelli, hot water, and salt. Bring to a boil, cover and reduce heat for 12-15 minutes. Fluff with a fork.
Add all the ingredients in a measuring cup. Whisk to combine.
Koshary is all about the layering! Add the rice with lentil mixture as the base, top with cooked pasta, chickpeas, and fried onions. Drizzle with tomato sauce and cumin sauce.