Cupcakes

Cup of Yum
1. Preheat the oven to 350F degrees. Line a 12 cavity muffin pan with muffin papers.
2. In a medium bowl whisk together the flour, cornstarch, baking powder and salt.
3. Then in a large bowl using an electric mixer beat together the butter, sugar and lemon zest until fluffy. Add in the egg whites and vanilla extract and continue mixing until combined.
4. Turn the mixer down to low speed and mix in about ½ of the sour cream followed by half of the flour mixture. Then turn off the mixer and scrape down the sides of the bowl. Repeat with the rest of the sour cream and flour mixture. Then turn off the mixer and stir in the lemon juice. Be careful not to over mix.
5. Spoon the batter into your prepared muffin pan, filling each muffin paper about ⅔ to ¾ full. You'll end up with 12-14 cupcakes total.
6. Bake in the preheated oven for 15-18 minutes or until an inserted toothpick comes out clean.

Strawberry Frosting

1. Core the strawberries to remove the green centers. Then puree in the food processor or blender until smooth. Then push the puree through a wire sieve to remove the seeds. You should have about ¾ cup of puree.
2. Transfer the puree to a small saucepan over medium heat and bring to a boil while gently stirring. Allow the mixture to boil for about 15-20 minutes, or until the mixture has reduced to about ⅓ to ¼ of the original volume (about ¼ cup). The thicker your puree is, the thicker your frosting will be.
3. Remove from the heat and allow mixture to cool fully. You can place it in the fridge or freezer to speed up the process.
4. In a large bowl beat the butter until fluffy, then beat in about 1.5 cups of the powdered sugar. Then turn the mixer down to low and beat in 2-3 tablespoons of the reduced strawberry puree. The mixture must be cold when it's added to the frosting, otherwise the frosting will separate.
5. Once added, beat in the rest of the powdered sugar and the whipping cream if necessary.
6. Frost the cupcakes either with a piping bag (I used a 1M tip) or with a knife.