Preheat your oven to 350°F (175°C) and grease a bundt pan with non-stick spray.
Open the cinnamon roll cans and set the icing packets aside. Cut each roll into quarters.
Combine sugar and cinnamon in a zip-top bag. Add dough pieces and shake to coat.
Place half of the coated dough into the bundt pan and sprinkle with half of the nuts (optional).
Mix melted butter, brown sugar, and vanilla in a bowl. Pour half of this mixture over the dough.
Add remaining dough and pour the rest of the butter mixture on top.
Bake for 35–40 minutes, until golden and cooked through.
Cool for 10 minutes, then invert onto a serving plate. Drizzle with warmed icing and enjoy while warm!