Preheat oven to 350 degrees.
Line a cupcake pan with cupcake liners or coat with nonstick cooking spray. In a large bowl, beat the butter and sugar together with an electric hand mixer on medium-high speed until fluffy, scraping down the sides of the bowl with a rubber spatula as necessary. Beat in the eggs and vanilla.
In a separate bowl, whisk together the flour, salt and baking powder. Beat the dry ingredients into the wet ingredients, alternately with the milk, until just combined. Fold Champagne until combined. The batter might be slightly lumpy. That's ok.
Pour cupcake batter 2/3 of the way full into the muffin pan. Bake 18-20 minutes until a tester comes out clean.
To make the frosting, cut the stems off of the strawberries and puree them in a blender until smooth. In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and powdered sugar together. Then beat in the strawberry puree until smooth. Add the heavy cream, one tablespoon at a time as necessary, until the desired consistency is achieved.
Fill a piping bag or Ziploc bag with the corner snipped off with the frosting. Pipe the frosting in a circular pattern on top of the cupcakes. Sprinkle with red or gold sprinkles. Top with strawberry slices.