Preheat the oven to 325°F and grease a 9x13 baking dish. Mix crushed churros or cinnamon sugar cookie crumbs, melted butter, sugar, and cinnamon until evenly combined.

Press the crumb mixture firmly into the greased 9x13 baking dish, using the back of a measuring cup to compact it. Ensure the surface is level so the cheesecake bars slice cleanly.

Beat softened cream cheese and sugar until creamy, smooth, and no lumps remain. Scrape down the bowl as needed for even texture.

Add eggs one at a time, beating well after each addition. Mix just until incorporated so the batter stays creamy, not airy.

Stir in vanilla extract, sour cream, and cinnamon until the batter looks uniform. The filling should be thick and glossy.

Pour the filling over the crust and tap the pan lightly to settle the surface. Watch for small air bubbles to rise and pop.

Bake at 325°F for 30-35 minutes, until the cheesecake is set but slightly jiggly in the center. You should see a firm edge with a gentle wobble in the middle.

Cool completely at room temperature, then refrigerate for at least 3 hours before cutting. Chilling firms up the bars for neat squares.

While the cheesecake is still warm, mix cinnamon, sugar, and melted butter. Sprinkle the cinnamon sugar topping evenly over the warm cheesecake so it clings.

Warm dulce de leche with cinnamon until loosened for drizzling. Drizzle the sauce over the bars before serving to highlight the churro crust and layers.