Before anything, preheat the Aebleskiver pan while making the batter.
In a large bowl, add the all-purpose flour, salt, and baking soda. Whisk to combine. In a glass measuring cup, measure out the whole milk then add in the vinegar. Stir to combine and then let stand for 7-10 minutes.
Separate the egg whites from the yolks. The yolks will go in with the flour mixture, and the whites will go into an electric mixer. Add in the milk vinegar mixture into the flour and egg yolks. Whisk to combine.
In the electric mixer, beat the egg whites to stiff peaks. You will need the egg whites to be as light and fluffy as possible. This will add air to the batter to create light and fluffy pastry balls.
Pour the beaten egg whites into the batter and gently fold in until combined. Do not mix aggressively because you will lose all of the air that was beaten into the egg whites.
In the preheated pan, spray cooking oil in each Aebleskiver hole then pour the batter in until just slightly below the top.
When the air bubbles in the batter begin to pop, take the kabob skewer and flip the Aebleskivers over to allow for the rest of the dough to cook and for the ball shape to take place.
When the Aebleskiver balls are thoroughly cooked, take out of the pan and place in a large bowl. Cover with a clean towel to keep the heat in and absorb extra moisture. When finished cooking all of the batter, sprinkle the Aebleskivers with powdered sugar. Serve immediately with fresh fruit and jam or jelly.
Personally, I think Aebleskivers are not good saved and reheated, but if you don’t mind leftovers then store in an airtight container for up to a week.