Prepare the strawberry layer
Preheat oven to 350°F (175°C).
Pour melted butter into the cake pan and sprinkle evenly with brown sugar. Arrange strawberry halves over the sugar layer.
Make the cake batter
In a bowl, whisk flour, baking powder, and salt.
In another bowl, beat butter and sugar until light and fluffy. Add eggs one at a time, then mix in vanilla.
Combine
Add dry ingredients alternately with milk, mixing until just combined. Do not overmix.
Bake
Gently spread batter over strawberries.
Bake for 40 minutes, or until a toothpick inserted in the center comes out clean.
Flip & serve
Let cake cool for 10 minutes, then carefully invert onto a plate.
Serve warm or at room temperature.