4apples, peeled, and sliced 1/4 inch thick (about 16 slices per apple)
For the crumble:
1stickbutter, cubed and softened100 g
Preheat oven to 180 C (350F)
To make the salted caramel:
In a medium saucepan, stir together the sugar and the water. Place the saucepan on the stove over medium high heat. Cook without stirring until sugar dissolves, then turns into the amber brown color of caramel. This will take around 10 minutes.
Removing the pan from the heat, drizzle in the heavy cream slowly whisking while doing so. Return to the heat, and continue whisking. The caramel might seize up initially but will then smooth out over the heat.
Add the butter, and whisk until combined. Remove from the heat, and whisk in the salt, rose water, and orange blossom water (if using). Let the caramel cool while you prepare the apples.
For the apples:
In a large skillet over medium heat (a 10 inch cast iron skillet if you have one), heat the 2 tbsp of butter until melted. Add the apple slices, and cook, stirring occasionally until apples have slightly softly, around 5-7 minutes. They don't need to fully soften as they will be baked in the oven.
After apple slices have cooked, sprinkle with the cinnamon. Add 1/2 cup of your prepared salted caramel sauce and stir to thoroughly coat the apples.
For the crumble:
Mix together the flour, oats, brown sugar, white sugar, cinnamon, nutmeg and salt until well combined. Add the cubed softened butter and using your fingertips, work the butter into the mix until the mixture looks like clumpy wet sand.
If using a cast iron skillet, evenly distribute the crumb topping right over the apple caramel mix in the skillet. If using a baking pan, transfer the apples to an 8 or 9 inch square baking pan, then cover with the crumb topping. Bake for 20-25 minutes until crumble is golden brown and apples are bubbling. Remove from oven and serve warm with extra caramel sauce and vanilla ice cream if desired.