My notes: Yes there is ONLY baking soda in these but it works. Do not try to add baking powder. I know you will look at this and think, “ don’t baked goods need baking powder or both powder and soda?” well yes, sometimes. It’s the vinegar that reacts with the soda, which helps with the proper leavening of the cake. These totally ROCK. They’re moist, dense, perfect texture and taste. Even 4 days after having been in my fridge, which normally dries them out, but they were still perfect. I have made them a few times now once I got 26 or 27 cupcakes and another time 28. Just depends on how full you fill the cups. I use a #16 ice cream/batter scoop to fill mine. One full scoop works and if I have batter leftover and some look to be less filled with batter than I try to even out with a spoon and add in more batter that way. I also like SLAM the cupcake pans down on my counter a few times ( just lift evenly and let drop) to help get some of the air bubbles out. I am not sure where I read this technique but it works and well its kind of fun to make the noise. Unless you bake while your baby/kids/husband/significant other is sleeping. They might not like it. Good luck and trust me you will LOVE this recipe. I do!!