Preheat your oven to 350°F (175°C). Line two standard cupcake pans with paper liners and set them aside. In the bowl of a stand mixer fitted with the paddle attachment—or using a large mixing bowl and a handheld electric mixer—beat the butter, vanilla extract, lemon extract, granulated sugar, and lemon zest together on medium speed until the mixture is light and fluffy, about 2 minutes. Add the eggs one at a time, beating well after each addition. With the mixer on low speed, blend in the sour cream, followed by the milk. Turn the mixer off.

Add 3 1/4 cups of cake flour, baking powder, baking soda, and salt directly into the bowl. Use a fork to gently combine the dry ingredients before folding them into the wet mixture. Using a rubber spatula, carefully fold the ingredients together until just combined—be careful not to overmix, as this can result in dense cupcakes.

In a separate small bowl, toss the raspberries with the remaining 3 tablespoons of cake flour. This helps prevent the berries from sinking during baking. Gently fold the floured raspberries into the batter with a rubber spatula, mixing only until evenly distributed.

Spoon the batter into the prepared cupcake liners, filling each about 3/4 full. Bake one tray at a time for approximately 22 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs. Allow the cupcakes to cool in the pan for 10 minutes, then transfer them to a wire rack to cool completely before frosting.

In the bowl of a stand mixer fitted with the paddle attachment—or in a large bowl using a handheld mixer—beat the softened cream cheese, butter, and lemon extract on medium-high speed until smooth and creamy, about 2 minutes. Reduce the speed to low and gradually add the sifted confectioners’ sugar. Add the fresh lemon juice and zest. Once all ingredients are incorporated, increase the speed to medium-high and beat for another 1–2 minutes until light and fluffy.

Once the cupcakes are fully cooled, frost them using a spatula or piping bag. Garnish with fresh raspberries or lemon slices for a decorative touch, if desired.

These cupcakes are best enjoyed the day they are made but can be stored in an airtight container in the refrigerator for up to 3 days. Allow them to come to room temperature before serving for the best flavor and texture.