Melt the margarine and mix with the sugar. Mix the apple cider vinegar with the milk, mash the bananas. Mix the flour with the baking powder and mix the wet and dry ingredients quickly with the wooden spoon. Fold in the blueberries.
Place the dough in a loaf pan lined with baking paper and bake in a preheated oven at 150 ° C top / bottom heat for approx. 60 minutes. After taking the chopsticks, take them out of the oven and let them cool down.