Combine frozen lemonade concentrate juice (set remainder aside for later use), cake mix, sour cream, cream cheese, and eggs.
Beat at low speed with a mixer until moistened. Beat on high speed for 3 minutes, stopping to scrape sides.
Spoon batter into 30 paper-lined muffins, filling each ¾ full.
Bake at 350° for 22 minutes or until a wooden toothpick comes out clean.
Cool for 5 minutes, then remove the cupcakes and let them cool.
Once the cupcakes have cooled completely, frost with your favorite frosting. I love using Raspberry Buttercream Frosting for these—it’s a deliciously sweet and fruity match for the lemonade cupcakes. (Find the Raspberry Buttercream Frosting recipe on the blog!)