On medium-high heat, heat oil in a medium-sized wok or pan, and then add the diced onions. Once the onions are golden brown, add the garlic. Saute till the garlic is aromatic, about 30 seconds.
Next, add the salt and turmeric, curry leaves, and chopped green chili. Saute for about a minute and then add the lauki and tomato. Stirfry for about a minute and then lower the heat to low and cover the pan.
Let cook for about 10 minutes till the lauki and tomatoes have softened.
Once ready, uncover the pan, increase the heat, dry out any excess water, and let the oil rise to the top. Garnish with cilantro and enjoy immediately.