Just as "well" as I can picture the face of anyone I know well enough.
I have prosopagnosia so I don't remember faces - in my imagination everyone face is a generic, gray field with attached pictures of details I remembered such as distinguishable hairstyle, haircolor, eye color, face shape(round, oval etc), nose shape, wrinkles, beauty spots, glasses etc. My own face remembering ability isn't any better than my remembering of the face of anyone I see daily and pay enough attention to.
I could draw it but I miss the placement and perspective. Face itself gets too big, eyes, nose and mouth too small and to close to each other, hair too short or too long etc.