Preheat oven to 350 degrees F. In a food processor, barely pulse together rolled oats, graham crackers, sugar, and salt. You do not want to end up with oat flour. Pulse just until the rolled oats are somewhat broken up. Add in melted butter and stir until mixture comes together. Press into four small tart pans with removable bottom.
Bake for 12-15 minutes until crust is set and golden brown. Crust may slightly puff up during baking. Use the bottom of a glass or measuring cup to gently press crust into shell. Set aside and allow to cool to room temperature before filling.
Whip cream cheese until smooth. Add maple syrup and cinnamon. Mix until incorporated. Add powdered sugar, vanilla and sea salt. Mix until smooth. Adjust thickness by adding additional powdered sugar a couple tablespoons at a time until desired sweetness/thickness is achieved.
Fill cooled graham oat crusts with maple cinnamon cream cheese. Spread into an even layer. Arrange sliced persimmons on top of cream cheese. Keep chilled until ready to use. Before serving, generously sprinkle sugar over persimmon and cream cheese. Use a kitchen torch to brûlée the sugar, being careful not to burn the crust. Serve immediately.