Heat oven to 350°. Line 12 standard muffin cups with paper liners. In medium bowl, whisk flour, baking powder, baking soda, and salt. In large bowl with mixer on medium, beat butter and sugar until light and creamy. Beat in eggs, 1 at a time, then vanilla. With mixer on low, alternately beat in flour mixture and sour cream until combined. Continue to beat on medium until batter is thick and smooth. Spoon batter into a zip-top bag. Snip a 1/2-inch corner from bag and fill liners slightly less than two-thirds full. Bake 24 to 26 minutes, or until lightly golden and a pick inserted in the center of a cupcake comes out clean. Cool in pan on a wire rack 5 minutes; remove cupcakes from pan and cool completely. Toss strawberries several times in a bowl with sugar and lemon juice until very syrupy. In large bowl, beat cream, confectioners? sugar and vanilla until soft peaks form. Use a skewer to poke several holes into top of each cupcake. Spoon some syrup from bowl over top, allowing it to absorb into cupcakes. Top with sliced berries and a dollop of cream. Arrange a few sliced berries in cream and drizzle with remaining strawberry syrup.