Boil the peeled bananas in water with salt. Add 1 teaspoon of milk to the water. When they are soft, let them cool and cut into 1-inch slices.  Mix the oil, vinegar, bay leaves, pepper, garlic, lemon juice and salt in a saucepan. Cut the onions into thin rings and add. Bring to a boil and then lower the heat. Cover and leave for half an hour on the stove. Let the mix cool and pour over the boiled bananas. Cover well and you can keep them for several days.