Create a new 400 x 150 file. Fill your image with #5C5C44.

With the rectangular tool, make a selection in the middle of the image. Then---and only then---go to Select > Modify > Smooth > 6 pixels.

Create a new layer and fill with white (or any color of your choosing).

Go to Select >Modify >Contract > 7 pixels. Immediately afterwards, Select >Modify > 6 pixels. Hit the delete button and you should end up with the image shown above.

Control + Click on the top layer to load the selection, go to Layer Styles and select Gradient Overlay. Make sure Black to White Gradient is selected (should be the default), click on the first color stop and use #787758. On the second (right) color stop, utilize #161511.

Deselect and you should have what is shown at left. The trick is to have your dark color on top and a lighter color on the bottom.

Use the magic wand and select the rectangle middle. Fill with black and deselect to the envy of all your friends.

With Lake Louise scenery as the backdrop.