First, prepare the caramel sauce. In a medium nonstick pot, combine the brown sugar and soy or coconut milk.
Turn heat on medium, and cook the caramel, stirring often, until thick and dark amber. This will take 10-15 minutes. Be careful not to burn it!
When ready, remove from heat and add in the vegan butter, vanilla, and pinch of salt. Set aside while you prepare the rest.
Preheat oven to 425F. Grab your thawed pie crust, and carefully roll it out to a rough circle about 12" across. Place on a piece of parchment or silicone liner on a baking sheet.
To prepare the apples, wash and slice them thinly. Place in a large bowl and toss with the additional brown sugar, flour, apple pie spice, vanilla, and lemon juice.
Mix until combined, then pour into the middle of your prepared crust.
Gently fold over the sides of the galette around the apple filling. To finish, brush the crust with some additional soy/coconut milk and sprinkle it with the white granulated sugar.
Bake galette for 35-40 minutes, until golden brown and crisp.
Serve topped with the vegan caramel sauce and ice cream!