Melt the butter and combine with brown sugar. Arrange loquats on a greased pan with cut sides down. Then pour the butter sugar mixture over the loquats.
For the cake:
In a bowl sift together flour with baking powder, baking soda, salt, and cinnamon.
In separate bowl cream butter with sugar until smooth and creamy (4-5 minutes). Then mix in the eggs and vanilla extracts. Combine dry ingredients with the mixture, then add the milk and mix again. Do not overmix the batter.
Pour the prepared batter over the loquats in the pan.
Bake in the oven for 40 minutes or until a toothpick comes out clean from the center of the cake.
Let the cake cool for 10 minutes then flip it over a plate (before the caramel becomes sticky!), serve warm or at room temperature.
Serve warm with a scoop of vanilla ice cream (optional).