01 - Preheat oven to 350°F. Line a 13x9 inch rimmed baking sheet with parchment paper.
02 - Arrange graham crackers in a single layer to completely cover the bottom of the pan.
03 - In a saucepan over medium heat, melt butter. Stir in brown sugar, maple syrup, and salt. Bring to a gentle boil, stirring constantly, and simmer for 2 to 3 minutes until slightly thickened.
04 - Remove saucepan from heat and stir in vanilla extract and chopped pecans until evenly combined.
05 - Pour the hot pecan mixture evenly over the graham crackers, spreading gently with a spatula to coat.
06 - Bake for 15 to 18 minutes until the topping is bubbling and golden brown.
07 - Remove from oven and cool for 10 minutes. Drizzle melted chocolate over the bark if desired.
08 - Allow to set completely, refrigerating for faster setting, then break or cut into serving pieces.