Preheat the oven to 190°C. Line a baking tray with parchment paper.
Cor the apples and cut them into very thin slices (you can use a mandolin).
Add dollops of honey onto the parchment paper, allowing enough space between them.
Scatter some walnut over the honey, then lay about 3 slices of apple on top. Sprinkle some cinnamon on top if liked
Unroll the pastry. Stamp out rounds, using a small bowl or a cup big enough to cover the apples.
Place the round over the apples and press down the sides gently.
Bake for 12-15 minutes, until golden, then remove from the oven.
Turn over the tarts. If you want them golden and caramelized, scatter some brown sugar on top and put them back in the oven for another 2 minutes.
Let them cool.
Meanwhile mix some icing sugar with some cinnamon powder.
When the tarts are cool, dust them with the sugar.