Preheat oven to 350*
Spray and 8 x 8 baking pan
In a large bowl whisk flour, baking powder, ½ tsp salt, 1 tsp cinnamon, sugar, milk, vegetable oil and vanilla until smooth. Pour into prepared pan.
Combine brown sugar, ½ tsp remaining salt and remaining 1 tsp cinnamon in a bowl and sprinkle over the top of the batter
Slowly pour the hot water on top of the sugar mixture
Place in oven and bake 45 min
Serve warm, with ice cream