In a bowl, combine the beaten egg, sugar, salt, pepper, milk, and finely chopped onion.

Add the cooked mashed squash to the mixture and mix well.

Gradually incorporate the self-rising flour into the squash mixture, ensuring there are no lumps.

Heat about 1/8 inch of salad oil in a large skillet over medium heat.

Once the oil is hot, drop spoonfuls of the squash mixture into the skillet, forming patties.

Gently flatten each patty to about 1/4 inch thickness using the back of a spoon or spatula.

Cook the patties until they are golden brown on the bottom, about 3-5 minutes.

Carefully flip the patties and cook until the other side is golden brown, about 3-5 minutes.

Remove the cooked patties from the skillet and place them on a paper towel-lined plate to drain excess oil.

Serve hot and enjoy!