Create a new file: File> New. Any size that will fit your text.

Choose the color you want your text to be then use the Text Tool to create the text. It will automatically be created on a new layer.

Create a new layer beneath the text layer.

Left-click the new layer. Then Ctrl-Click the text layer. Select> Modify> Expand, 1 or 2 pixels expands the selection to just a bit larger than the text. Change the Foreground Color to the color you want for the text border: Edir> Fill> Foreground Color.

Ctrl-U will allow you to change the color of either layer to suit your preferences.