In a small bowl, whisk together eggs, sour cream, and vanilla until smooth.
In the bowl of a stand mixer, mix flour, baking powder, baking soda, salt, sugar, lemon zest, and butter on high speed until fully combined.
Mix wet ingredients into dry ingredients a little bit at a time until just combined.
Mix in milk until just combined.
Use a spatula to fold in chopped strawberries.
Fill cupcake liners halfway full.
Bake for 25 minutes or until a toothpick inserted into the center of a cupcake comes out clean.
Remove cupcakes from cupcake tin immediately and set on the counter to cool.
Strawberry Frosting Instructions
Beat butter for three minutes (or until light and fluffy) in the bowl of a stand mixer fitted with the paddle attachment.
Mix in strawberry puree and salt.
Mix in powdered sugar a little bit at a time.
Spread or pipe on cooled cupcakes.
Notes
For the cupcakes:
You can use all-purpose flour in this recipe instead of cake flour. The results won't be dramatically different. The cake will just be a little more dense.
Yogurt can be substituted 1:1 for the sour cream.
Be careful not to overmix to keep your cupcakes from getting gummy.
Only fill your cupcake liners halfway. To be completely certain that you are filling the right amount, bake a single test cupcake before baking the rest of the batch.
Make sure the cupcakes are completely cool before frosting so that the frosting doesn't melt.
For the frosting:
Be sure to beat the butter for at least three minutes so it is light and fluffy.
Use less ripe strawberries. Riper strawberries tend to be more moist and could end up making the frosting too wet.
Add the powdered sugar a little bit at a time and always start on low speed to keep it from making a mess in your kitchen.
While I don't recommend frozen berries, if your strawberries were frozen, be sure to defrost them and drain off any excess liquid before using them.