In a large mixing bowl, combine the corn masa flour, warm water, salt, black pepper, garlic powder, and vegetable oil. Mix until a smooth dough forms.
In a separate mixing bowl, combine the diced fish, onion, garlic, cumin, coriander, oregano, salt, and black pepper. Mix well.
Divide the corn masa dough into 8 equal portions and roll each portion into a ball.
Flatten each ball into a circle and place a spoonful of the fish mixture in the center.
Fold the dough over the filling and press the edges to seal.
Heat the vegetable oil in a deep frying pan over medium-high heat.
Fry the Panades in the hot oil for about 3-4 minutes on each side or until golden brown and crispy.
Remove the Panades from the oil and place them on a paper towel-lined plate to drain excess oil.
Serve hot and enjoy!