01 - Preheat oven to 350°F. Line a 9x13-inch baking pan with parchment paper and lightly grease.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, and salt.
03 - In a large bowl, cream butter and granulated sugar until light and fluffy. Beat in eggs, one at a time, then mix in vanilla.
04 - Alternately add the dry ingredients and milk to the creamed mixture, starting and ending with flour. Mix until just combined.
05 - Spread batter evenly in the prepared pan. Bake for 22–25 minutes, or until a toothpick comes out clean. Allow to cool completely in the pan on a wire rack.
06 - While the cake cools, toss strawberries with sugar and lemon juice in a bowl. Set aside for at least 20 minutes to macerate.
07 - In another bowl, whip heavy cream, powdered sugar, and vanilla until medium-stiff peaks form.
08 - Once the cake is completely cool, spread the whipped cream evenly over the cake. Spoon the macerated strawberries and their juices over the top.
09 - Slice and serve immediately, or refrigerate until ready to serve.