Preheat your oven to 350°F (175°C) and scatter sliced butter evenly across the bottom of a 9×13 inch baking dish. Bake for about 5-7 minutes until the butter is melted and bubbling.

In a large mixing bowl, combine flour, granulated sugar, baking powder, and salt. Whisk until blended, then add milk and vanilla extract, stirring gently until combined.

Carefully pour the batter over the melted butter without stirring, covering the entire surface.

Sprinkle chopped pecans and light brown sugar over the batter. Gently pour boiling water over the mixture.

Sprinkle cinnamon on top, then bake for 40-45 minutes, until the center is set but gooey.

Allow the cobbler to cool for about 10 minutes before serving.