01 - Preheat oven to 350°F. Grease and line two 8-inch round cake pans with parchment paper.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl. Set aside.
03 - Beat softened butter and granulated sugar in a large bowl until light and fluffy, approximately 3-4 minutes.
04 - Add eggs one at a time, beating well after each addition. Mix in vanilla extract.
05 - Alternately add flour mixture and buttermilk to the butter mixture, beginning and ending with flour. Mix until just combined.
06 - Divide batter evenly between prepared pans. Bake for 22-25 minutes or until a toothpick inserted into the center comes out clean. Cool in pans for 10 minutes, then remove to wire racks to cool completely.
07 - Combine sliced strawberries, sugar, and lemon juice in a bowl. Let stand for at least 20 minutes, stirring occasionally, until strawberries release their juices.
08 - In a chilled bowl, whip heavy cream, powdered sugar, and vanilla extract until stiff peaks form.
09 - Place one cake layer on a serving plate. Top with half the strawberry mixture and juices, spreading evenly. Spread half the whipped cream over the strawberries. Place second cake layer on top. Add remaining strawberries and finish with remaining whipped cream.
10 - Refrigerate assembled cake for at least 1 hour before slicing to allow flavors to meld and cake to set.