Preheat your oven to 350°F (175°C). Grease a baking dish.
In a mixing bowl, combine flour, baking powder, salt, and granulated sugar. Stir in milk, vanilla, and melted butter until well mixed. Pour the batter into the prepared baking dish.
Sprinkle chopped pecans and brown sugar over the batter. Carefully pour boiling water over the top without stirring.
Bake for 40 minutes until the top is golden brown.
Notes
Serve warm with whipped cream or ice cream for a delicious treat.