It worked wonderfully, they came out beautiful, if I was a little less lazy I could have arranged the apples a bit more carefully.
I was also making the caramel toffee cheesecakes from buff chickpea, so that caramel sauce doubled up nicely.
There isnt really a recipe, you take about 2 teaspoons of caramel sauce, put in the bottom of a muffin pan, chop 3 apples and cook until a little tender (I dont think I needed to do this, I could have sliced them thinner and they would have been fine).
Pop the apple slices into the pan, then add another drizzle of caramel sauce.
Top with a circle of either puff pastry or shortcrust pastry and bake for around 30 mins at 350f. Allow to cool, then place a baking sheet over the top, flip over and tap really hard to remove the tarts.
There might be a few bits of apples left in the pan, but they are really easy to pop back on the tarts.