Preheat oven to 350°F (175°C) and generously grease and flour a 10-inch bundt pan.

In a large mixing bowl, whisk together 3 cups flour, granulated sugar, salt, and baking powder.

In a separate bowl, whisk together 1.5 cups milk, eggs, and 2 teaspoons vanilla extract.

Gradually stir the wet ingredients into the dry ingredients until combined, then fold in the melted butter.

In a small bowl, prepare the filling by mixing softened butter, brown sugar, 2 tablespoons flour, and cinnamon until a thick paste forms.

Pour half of the cake batter into the prepared bundt pan.

Drop spoonfuls of half the cinnamon filling over the batter and swirl gently with a knife.

Pour the remaining batter over the filling, then top with remaining cinnamon filling and swirl again.

Bake for 50 to 60 minutes or until a skewer inserted into the center comes out clean.

Allow the cake to cool in the pan for 15 minutes before inverting onto a wire rack.

In a medium bowl, whisk together cream cheese, powdered sugar, 1 tablespoon milk, and 1/2 teaspoon vanilla until smooth and pourable.

Drizzle the cream cheese glaze over the cake while it is still slightly warm to allow it to set.