Step 1: Get things prepped: Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper or a silicone baking mat. Gently unroll the sheet of crescent roll dough onto the prepared baking sheet, laying it out flat.
Step 2: Butter it up: Use a pastry brush to evenly coat the entire surface of the crescent roll dough with the melted butter, getting right to the edges.
Step 3: Sprinkle the sweet stuff: In a small bowl, whisk together the granulated sugar, cinnamon, and optional salt. Sprinkle this mixture evenly all over the buttered dough.
Step 4: Bake to golden perfection: Slide the sheet into your preheated oven. Bake for about 12–15 minutes, until the edges are golden brown and crisp and the center is cooked through. Keep an eye on it starting around 10 minutes.
Step 5: Cool down (a little): Carefully remove the hot baking sheet from the oven. Let the cinnamon sugar pizza cool right on the sheet for about 5–10 minutes to help it firm up slightly before slicing.
Step 6: Whip up the icing (if you're using it): While your pizza is cooling, whisk together the powdered sugar, milk (or cream), and vanilla extract in a small bowl until smooth and pourable. Add a tiny bit more milk if too thick, or more powdered sugar if too thin.
Step 7: Slice and drizzle: Once cooled slightly, use a pizza cutter or knife to slice the pizza into triangles or squares. Drizzle the icing generously over the sliced pizza.
Step 8: Serve warm! Enjoy warm for the best taste and texture.