01 -
Preheat the oven to 175°C. Grease a 33x23 cm rectangular baking pan.
02 -
In a large mixing bowl, whisk together all-purpose flour, salt, granulated sugar, and baking powder until evenly blended.
03 -
Add milk, eggs, and vanilla extract to the dry mixture. Stir just until combined; do not overmix.
04 -
Gently fold in melted unsalted butter, mixing until the batter is smooth and uniform.
05 -
Pour the prepared batter evenly into the greased baking pan, smoothing the top with a spatula.
06 -
In a separate bowl, blend brown sugar, ground cinnamon, and room temperature butter until a thick, spreadable paste forms.
07 -
Distribute spoonfuls of the cinnamon paste over the batter. Using a knife, gently swirl it through the batter to create a marbled effect.
08 -
Bake for 28 to 32 minutes, or until a toothpick inserted in the center comes out clean and the cake springs back lightly.
09 -
While the cake bakes, whisk together powdered sugar, milk, and vanilla extract in a medium bowl until the icing is smooth and pourable.
10 -
Remove the cake from the oven and allow it to cool in the pan for 10 to 15 minutes. Drizzle the prepared icing evenly over the warm cake surface.
11 -
Let the icing set. Slice the cake into squares and serve warm or at room temperature.