Preheat the Blackstone pizza oven on the lowest setting.
In a large bowl, mix together the sliced sweet potatoes, melted butter, 1 cup brown sugar, 1 teaspoon cinnamon, cayenne pepper, and vanilla.
Arrange the sweet potatoes in a baking dish by stacking the slices and placing them vertically (edge-side up). Pour any remaining butter mixture over the potatoes, cover the dish with foil, and bake for 30–40 minutes.
In a separate bowl, combine the chopped pecans, ½ cup brown sugar, flour, room-temperature butter, and ½ teaspoon cinnamon with a fork until a crumbly mixture forms.
Remove the sweet potatoes from the oven and uncover the dish. Once the potatoes are fork-tender, spread the crumble mixture evenly over the top. Return the dish to the oven, uncovered, for 4–6 minutes or until the topping is golden brown.