Preheat oven: Preheat your oven to 350°F (175°C). Place the melted butter into the bottom of a 9x13-inch baking dish, making sure it evenly coats the base. Do not mix the butter into the batter—this layer helps create the cobbler texture.

Prepare the batter: In a large mixing bowl, combine flour, granulated sugar, baking powder, salt, and cinnamon. Stir well to distribute the dry ingredients evenly. Pour in the milk and vanilla extract, then mix until a smooth batter forms. Avoid overmixing to keep the texture light and tender.

Assemble the cobbler: Carefully pour the batter over the melted butter in the baking dish. Do not stir—the batter will naturally spread over the butter as it bakes, forming the cobbler layers.

Add the cinnamon sugar topping: In a small bowl, mix together brown sugar, granulated sugar, and cinnamon. Sprinkle this mixture evenly over the top of the batter, covering as much surface as possible for a rich, sweet crust.

Add hot water: Gently pour the hot water over the entire dish. Do not stir or mix. The water will look unusual on top, but it will transform during baking into a gooey sauce underneath the cobbler.

Bake the cobbler: Place the dish in the preheated oven and bake for 35–40 minutes, or until the top is golden brown and set. The center should still be slightly soft, and the edges should be bubbling. Allow it to cool for about 10–15 minutes before serving so the layers can settle and thicken.

Serve: Serve warm, preferably with a scoop of vanilla ice cream or a drizzle of cream for the best snickerdoodle-inspired experience.