This is the emergency kit you never knew you had. Baking soda lurks in almost every baking pantry. Team it up with fresh lemon juice or apple cider vinegar, and you get an instant fizz—that’s your rise.
For a general rule: 1 teaspoon of baking powder = ¼ teaspoon baking soda + ½ teaspoon lemon juice (or vinegar). Mix them into the wet ingredients first, then add flour. Pop the batter in the oven immediately. The reaction starts the second those two meet, so don’t dawdle.
Fun fact: This same reaction is used in homemade rockets for science fairs. Your muffins are essentially small, delicious rockets.
