In a large bowl, combine 1 cup of flour, baking powder, baking soda, and salt.

Gradually whisk in water until the mixture is smooth.

Peel the bananas.

Cut each banana crosswise into three pieces, resulting in a total of 12 pieces.

Lightly coat the banana pieces with the remaining 1/2 cup of flour.

Heat vegetable oil in a wok or deep fryer over medium-high heat until it reaches 375°F (190°C).

Dip each banana piece into the flour-water mixture, ensuring it is completely coated.

Carefully place 4 to 6 banana pieces at a time into the hot oil.

Fry for 3 to 5 minutes, or until golden brown.

Remove the fritters from the oil and drain on absorbent paper to remove excess oil.

Serve the banana fritters warm, optionally with vanilla ice cream.