Peel, core, and slice the apples evenly
Melt butter in a skillet over medium heat
Add the apple slices to the skillet
Sprinkle sugar over the apples
Add a pinch of salt
Stir gently to coat the apples
Cook until the apples soften and the sugar turns golden
Add cinnamon or vanilla if desired
Cook a little longer until the apples are caramelized
Remove from heat and serve warm