Preheat oven to 350 degrees Fahrenheit (180 degrees Celsius).

Divide cooked lukshen into two medium-sized bowls.

In a large frying pan, heat oil over medium flame and fry onions until they begin to turn golden, about 20 minutes. Remove half the onions from the frying pan and add to one of the bowls of lukshen.

Squeeze the liquid from the thawed spinach and add it to the onions in the frying pan. Sprinkle with salt and pepper, to taste. Continue to cook for two minutes. Remove from heat and add mixture to the second bowl of lukshen.

Add four eggs, one teaspoon salt, and half teaspoon pepper to each bowl and mix well. Add half cup brown sugar to the onion-lukshen mixture.

Pour the spinach mixture into the bottom of two greased loaf pans or one 9×13-inch (23×33-cm) baking pan. Then add the onion mixture. Alternatively, you can do four layers — half the spinach mixture, half the onion mixture, then half spinach and half onion.

Bake for 45 minutes to an hour.