In a deep-fryer or heavy-bottomed pot, heat enough peanut oil to come halfway up the sides of the pot, to 350 degrees F.
Peel the plantains and slice them into 1 1/2-inch chunks. Put the plantains into the fryer and fry until just golden brown, about 2 minutes. Stir the garlic and the water together in a medium bowl. Remove the plantains from the fryer and drain on a paper towel lined sheet tray. With the smooth side of a meat mallet, smash the plantain until it's flattened. Add them to the garlic water and let them soak for 1 minute. Remove the plantains from the water and pat dry with paper towels. Return to the fryer and continue to fry until golden brown and crisp, about another 2 minutes. Transfer the plantains to a serving bowl and season with salt. Serve hot.