Preheat oven to 350°F. Spray a standard loaf pan with nonstick cooking spray and line with parchment paper.
In a small bowl, stir together the sugar and cinnamon. Reserve 1 teaspoon of the mixture.
Add the remaining cinnamon sugar to the softened butter and mix until combined. Reserve 1 tablespoon of the butter mixture for the top.
Unroll each can of crescent dough, keeping the seams together to form rectangles.
Divide the butter mixture evenly between both rectangles and spread it out evenly.
Roll each rectangle back up tightly into logs. Place them side-by-side, seam-side down, in the prepared loaf pan.
Spread the reserved butter mixture over the top.
Bake for 40–45 minutes, tenting with foil halfway through if the top starts to brown too quickly.
Remove from the oven and immediately sprinkle with the reserved teaspoon of cinnamon sugar.
Let cool in the pan for 10 minutes, then lift out using the parchment. Slice and serve warm.
