Preheat the oven to 325 degrees F. Line 2 muffin pans with cupcake liners.
In a medium bowl, sift together the flour, baking powder and salt. Set aside.
In the bowl of an electric mixer fitted with the paddle attachment, cream the butter and granulated sugar until pale and fluffy. Add the eggs, one at a time, beating well after each addition. Scrape the bowl as needed. Beat in the lemon zest and vanilla extract until combined. With the mixer on the lowest speed, add the flour mixture in three additions, alternating with two additions of the buttermilk and lemon juice. Mix until just combined after each addition. Scrape the bowl as needed. Gently fold in the raspberries.
Fill the cupcake liners three-quarters full with batter and bake until a wooden toothpick inserted in the center comes out clean, about 25 minutes. Transfer the pans to wire racks to cool completely before frosting.
Frost the cupcakes with the Raspberry-Balsamic Cream Cheese Frosting.
In a small bowl, mix the raspberries with the granulated sugar and let stand for 15 minutes.
Place the raspberries in a small saucepan and add 1 tablespoon of the balsamic vinegar. Let simmer over medium heat for 15 minutes; the raspberries should cook down and create a sauce. Then crush the berries or run through a blender for a smoother frosting. Set aside to cool.
Mix the remaining 3 tablespoons balsamic vinegar into the raspberry sauce and set aside.
In a large bowl or the bowl of an electric mixer fitted with paddle attachment, beat the cream cheese and butter until creamy. Add 1/2 cup of the powdered sugar and beat until combined. Add the raspberry sauce and beat until combined. Add the remaining powdered sugar, a bit at a time, and beat until creamy. Add more sugar if a thicker consistency is desired.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.