Preheat the oven to 350°F.
Peel and core the apples. Slice very thinly, set aside.
In a large bowl stir together the eggs, sugar, beer, butter, flour and salt.
Add the apples, toss to coat.
Line a large (10 x 5) loaf pan, or an 8x8 square pan with parchment, spray with cooking spray.
Add the apple mixture to a the prepared pan.
Bake for 60 minutes or until the cake as set. Allow to cool, remove from pan. Refrigerate until ready to serve.
Add the brown sugar, butter and beer to a saucepan over high heat. Boil for two minutes, remove from heat. Stir in the vanilla and heavy cream, return to heat and bring to a boil again. Boil for one minute, remove from heat, allow to cool.
Pour the caramel over the cake, slice to serve.