Combine the cake flour and salt in a bowl—whisk to blend and set aside.

Heat the oven to 325 F and spray an 8 1/2 -by-4 1/2-inch loaf pan with baking spray. Line the bottom with parchment paper.

In a mixing bowl with an electric mixer, combine the butter and cream cheese. Beat on medium speed until smooth and creamy. Add the brown sugar and beat on medium speed for 3 minutes, until light and fluffy.

Add the eggs, one at a time, beating well after each addition.

With the mixer on low speed, add the flour mixture in 3 stages, alternating with the milk and vanilla, and mixing just until the flour is almost blended into the batter. Alternatively, use a spatula to mix the flour and liquids into the creamed mixture.

Turn the batter into the prepared loaf pan and spread evenly.

Bake for about 1 hour, or until a wooden skewer or toothpick comes out clean when inserted into the center of the cake.

Cool in the pan on a rack for 10 minutes, then carefully loosen the sides with a spatula and turn out of the pan.