Wel, as you can see, it’s a little beige in places but it’s taken a long time to find that out.
In 2015, multispectral images were sent back to Earth by NASA’s New Horizons spacecraft as it shot by Pluto at 80,000km/h. But processing these (in order to approximate what the human eye might see) took time. To wit:
The result featured here, released three years after the raw data was acquired by New Horizons, is the highest resolution true colour image of Pluto ever taken. Visible in the image is the light-coloured, heart-shaped, Tombaugh Regio, with the unexpectedly smooth Sputnik Planitia, made of frozen nitrogen, filling its western lobe. New Horizons found the dwarf-planet to have a surprisingly complex surface composed of many regions having perceptibly different hues. In total, though, Pluto is mostly brown, with much of its muted colour originating from small amounts of surface methane energised by ultraviolet light from the Sun.
Full sized image here.