Preheat the oven to 190°C (375°F). Roll your pastry on a clean, lightly floured surface so that it is 9 inches (23 cm) across. You can use the ring of a 9-inch fluted tart pan to create a lovely edge to the pastry. Prick the pastry with fork and chill until ready to use.
Peel, half and core your apples. Melt 1 tbsp (15 g) of the butter and pour this over the apples. Add 1 tbsp (13 g) sugar and toss the apples to coat. Set aside.
Heat your skillet or oven safe pan to medium high heat. Tip in the remaining butter, sugar and lemon juice. Once it is bubbling at the edges (about 4-5 minutes), add the apples, curved side down. Increase the heat to high and cook for 2-3 minutes or until vigorously bubbling at the edges of the pan. Place pan in the oven (without pastry) in the oven to bake for 15 minutes.
After 15 minutes, take out your pan and place your chilled pastry on top of the apples. Tuck the edges in a little. Return pan to the oven and bake for 30-35 minutes or until the pastry is golden brown.
Let your tarte cool for at least 20 minutes before loosening from pan. Use a palette knife to loosen apples that might stick to the sides. Using a tea towel, place a large plate over the pan and invert both. Lift your pan to reveal your tarte.