Preheat the oven to 350 degrees.
In a heavy bottom saucepan heat the sugar and water over medium high heat. It will boil for several minutes and then begin to turn golden brown. Once it turns golden remove from heat and begin whisking while adding in the heavy cream. The mixture will bubble and spit so be careful but whisk constantly.
Add in the butter, vanilla, and sea salt then place over low heat, whisking frequently, until butter is melted and the caramel sauce is well combined. Remove from heat.
To make the apples heat a fry pan over medium heat (I used Swiss Diamond 11 inch fry pan). Add the butter and melt completely. Add in the apples, apple pie spice, and salt and cook over medium heat for 5 minutes, stirring occasionally, or until the apples begin to soften.
Pour half of the homemade caramel sauce into the fry pan with the apples and mix well. Remove from heat.
Combine all ingredients for the crumble and mix until a crumble forms. Sprinkle over top of the apples in the fry pan and put the pan in the oven.
Cook for 20 minutes.
Turn the oven to broil and broil for 1-2 minutes or until the crumble is golden brown.
Remove from oven (using pot holders!) and drizzle with remaining caramel sauce.
Serve warm. Top with ice cream if desired.