1. Prepare the strawberries: In a large bowl, combine strawberries, granulated sugar, lemon juice, salt, and cornstarch. Toss gently and let macerate for at least 15 minutes. Set aside.
2. Preheat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans. Press 3 tablespoons of coarse sugar into the bottom of each pan for a textured crust.
3. Prepare the cake: In a bowl, cream the butter and 1 1/2 cups granulated sugar until light and fluffy. Add eggs one at a time, beating well after each addition.
4. In another bowl, sift together cake flour, baking powder, baking soda, and salt. Alternately add the dry ingredients and the sour cream to the butter mixture, mixing until just combined. Stir in the milk and vanilla extract until smooth.
5. Divide the batter between the prepared pans. Smooth the top and sprinkle the remaining 3 tablespoons of coarse sugar over the batter.
6. Bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean. Let the cakes cool in the pans for 10 minutes, then run a knife around the edges and turn out onto a wire rack to cool completely.
7. Prepare the whipped cream: In a cold mixing bowl, whip the heavy whipping cream until soft peaks form. Add the cream cheese, salt, and powdered sugar and continue whipping until stiff, glossy peaks form.
8. Assemble the cake: Place one cake layer on a serving plate. Spread half the whipped cream on top, then layer half the macerated strawberries, pressing down slightly. Add the second layer of cake and spread the remaining whipped cream on top. Cover the strawberries with the second layer of strawberries and gently press to adhere.
9. Chill the cake in the refrigerator for at least 2 hours to allow the layers to set before serving.