For the Cupcakes: Adjust oven rack to middle position and preheat oven to 350°F (180°C). Line cupcake tin with liners and lightly coat with baking spray.
Whisk flour, baking powder, baking soda, and salt together in medium bowl; reserve. Combine buttermilk and vanilla in liquid measuring cup; reserve.
Beat butter and sugar on medium speed until light and fluffy, about 2 minutes. Add eggs, one at a time, beating well after each addition. Add flour mixture in three additions, alternating with buttermilk mixture, scraping down sides and bottom of bowl with rubber spatula as needed.
Divide batter equally among prepared tin. Bake until tester inserted in center of cupcakes comes out clean, about 20 minutes. Transfer cupcakes to cooling rack and cool 10 minutes in pan. Turn cupcakes out directly onto racks, then invert so the tops are facing up. Cool completely, about 30 minutes.
For the Filling and Assembly: Toss strawberries with sugar, lemon juice, and salt in medium bowl; set aside.
Whip cream cheese and confectioners’ sugar on medium speed until light, about 30 seconds. Add 1/4 cup cream and beat until combined, about 30 seconds. Add remaining cream and beat until soft peaks form, 1 to 2 minutes.
To serve, slice cupcake tops off with serrated knife. Arrange strawberries on cupcake base, dollop with cream and place tops over cream. Serve.
12-cup standard muffin tin, 12 cupcake liners, electric mixer, rubber spatula, cooling rack
