Put mortar on cement board for outdoor kitchen
It would be like doing Sheetrock. Make sure to have the edges along the sides of the cement board meet. (Not the ends). Then use Fiberglas mesh tape and skim coat. If you use the edges there is a slight indent so the joint won't be noticeable. Butting the ends will cause a bulge that will require a much thicker coat to hide the joint. If you don't use the mesh tape it will crack and every seam will show in a few months. tape like this.