One workaround is to create your text, then copy and paste the text to create a second copy. Select all the text in the copy, then in the Format menu, under the Font flyout menu, choose "Outline". This will change the text so that it is empty but for the letter outlines, which will be in the text colour chosen. Set the text colour to black, and then move the outlined text on top of the original text. You should now have the original text with a black outline around it.
As far as I can determine, there is no way to set the thickness of the outline, and the process itself is a bit cumbersome, so this isn't ideal, but it produces reasonable results.