Preheat your oven to 350°F (175°C). Grease a 9-inch round cake pan with cooking spray or butter.
In a small bowl, mix the melted butter and brown sugar until well combined. Pour this mixture into the bottom of the prepared cake pan.
Arrange the halved strawberries in a single layer on top of the brown sugar mixture, cut side up.
In a large mixing bowl, whisk together the flour, granulated sugar, baking powder, and salt.
In another bowl, combine the milk, eggs, and vanilla extract. Add this mixture to the dry ingredients and stir until just combined. Be careful not to overmix.
Pour the batter evenly over the strawberries in the cake pan, spreading it gently to cover the fruit.
Bake for 35-40 minutes, or until a toothpick inserted into the center comes out clean.
Remove the cake from the oven and let it cool in the pan for about 10 minutes. Then, carefully invert the cake onto a serving plate while it’s still warm.