Pick any brush you like, switch to image-based color and load a picture:

You can rotate and place it as you want in your canvas and adjust the opacity of the displayed source picture.
And here is the trick: in the "Color Shifting" tab, check enable and push the value slider all the way to the left. That will simply make any picked color black:

Then just draw over your picture:

Once you're done, be sure to uncheck the "enable" box in the color shifting tab or any color you use with that brush afterwards will be black too!