Remove puff pastry from the freezer and thaw according to package instructions.
In a medium bowl, combine sugar, cinnamon and half the butter.
Peel apples, cut in half and core. Slice apples and combine with the sugar mixture. Set aside while you prepare the pastry.
Cut through the puff pastry sheet, 1/2 inch (1.5cm) in from the edge all around but leaving two opposite corners uncut. Bring one edge over to the other side and repeat on the opposite side. Check the instruction photos above. This is optional but I like to make the edge thicker.
Brush all over with the remaining melted butter.
Sprinkle ground almonds evenly over the pastry avoiding the doubled edge.
Arrange apple slices neatly over the ground almonds.
Bake 30-35 minutes until golden brown and the pastry is puffed and crisp. Check underneath to see that the pastry has browned, if not bake for another 5-10 minutes but lower the oven temp to 350ºF/180ºC.
Remove tart from the oven. Heat apricot conserve in the microwave for 15-20 seconds or until melted (or in a small saucepan over gentle heat). Brush apples with melted conserve.
Transfer the tart to a wire rack to cool.
Divide into four portions and serve with ice cream or cream.
Video
Notes
Tips for success
This recipe uses pre-rolled frozen puff pastry easily available at the supermarket.
Keep the pastry cool.
The key to this recipe is to use a hot oven and keep the pastry cold for maximum puff.
Ovens can vary quite a bit so keep an eye on the tart and use your senses to judge if it needs more or less time in the oven.
Can I use other types of apples? I really like using granny smiths but that's my personal preference. You could use pink lady, gala, golden delicious or fuji. Don't limit yourself. This is such a simple recipe, try with your fav apple.Cutting and twisting the puff pastry looks complicated - do I have to do it?Absolutely not. That is entirely optional. I like the edge to be thicker which is why I do that. If you prefer, simply fold the edge over to create a thicker edge.How do I store this tart?Truthfully, this tart is best eaten soon after it cools (or warm). But if you do happen to have leftovers, store on a plate covered with plastic wrap in the fridge.