Preheat oven to 350°F and grease an 8×8 or 9×13 pan.
Mix brown sugar, corn syrup, ¼ cup melted butter, vanilla, eggs, salt, and cinnamon.
Fold in half the pecans and pour mixture into the prepared pan.
Sprinkle dry cake mix evenly on top. Do not stir.
Drizzle remaining ¼ cup melted butter evenly over the cake mix.
Top with remaining pecans.
Bake 30–35 minutes or until golden and set.
Let cool for 10 minutes before serving.
