Peel the super-ripe bananas into a large mixing bowl and mash them thoroughly with a fork until smooth with only slight texture remaining.
Stir in the sugar, salt, and nutmeg or vanilla extract until evenly combined throughout the banana mash.
Gradually add the flour in stages, stirring well after each addition, until you have a thick, scoopable batter that holds a soft mound shape without spreading immediately.
Let the batter sit for 2 minutes so it firms up slightly, making it easier to scoop into even portions.
Pour about 2 inches of vegetable or avocado oil into a deep skillet or pot and heat over medium heat for 3 to 4 minutes until a small drop of batter sizzles and rises to the surface within seconds.
Scoop small portions of batter with a spoon or gently squeeze balls by hand into the hot oil. Fry in batches of 5 to 6 pieces at a time, avoiding crowding the pan.
Fry for 10 to 15 minutes, turning occasionally with a slotted spoon, until the fritters are deep golden or coffee-brown all over.
Remove with a slotted spoon and transfer to a wire rack to cool for 3 to 5 minutes before serving.
