Preheat the oven to 180C/350F and spray a 12 inch skillet with cooking spray.
Make the filling, place the chopped apples, cinnamon, sugar, flour and salt into a medium sized bowl and stir to coat. Add in the vanilla and continue to stir until all of the apples are coated in the sugar mixture. Leave to one side.
Make the topping: Place the flour, sugar, baking powder and salt into a medium sized bowl and stir briefly to combine.
Add in the eggs and stir until the mixture becomes crumbly. Pour in the cooled melted butter and mix until a sticky batter forms. It will be a thick batter.
By this stage the apple mixture should be slightly glossy from the sugar, tip this mixture into your prepared skillet and spread into an even layer.
Using a dessert spoon, drop spoonfuls of batter onto the apples - it's OK if it doesn't completely cover the apples, mine did pretty much, but it will spread, so don't worry!
Place into the oven for 35-40 minutes until the filling is bubbling around the edges and the top is golden. An inserted skewer into the cobbler layer should come out clean.
Leave to cool for at least 45 minutes before serving. You can serve warm with ice cream or at room temperature. If you have leftovers, transfer them to an airtight container as if you leave it in the skillet, it will start to taste metallic.
Store in the fridge for 4 days, serve at room temperature or warmed in the microwave.