Preheat the oven to 350º. Line the bottom of a 9-inch cake pan with parchment paper, then butter and flour the pan.
In the bowl of an electric mixer, cream butter until smooth, add sugar and beat until well combined, 2-3 minutes. Add eggs one at a time, beating well after each addition. Add sour cream and vanilla and beat until well combined.
In a small bowl, whisk together the flour, baking soda, cornstarch, and salt. Add to butter mixture and mix until well combined. Spread into the prepared cake pan.
Bake for 30-35 minutes until a toothpick comes out clean. Let cool on a wire rack for 10 minutes then remove from the pan, remove the parchment paper and let cool completely.
Add sugar to the strawberries in a medium bowl and let them sit for 10 minutes. Mash slightly with a potato masher, leaving chunks of strawberries.
Once the cake has cooled, slice it in half with a serrated knife. Lay both layers cut side up. Spread the strawberries on each half and place in the freezer for 15 minutes.
For the frosting, beat the cream cheese and butter until smooth. Then add powdered sugar, vanilla, and salt and beat until creamy.
Remove the cake halves from the freezer and spoon a third of the frosting over one of the layers of strawberries. Use an offset spatula to spread the frosting over the strawberries gently. Add the second layer on top with the strawberry layer facing up. Add the rest of the frosting to the top and sides of the cake. It will not be smooth due to the chunks of strawberries. Keep refrigerated until ready to serve.