An LED lamp for illuminating a surface under a flat angle in linear lighting applications such as cove lighting and wall washing is provided. It produces a uniform intensity distribution and a uniform color output throughout the beam pattern of the light beam produced by a multi-color LED light source. The lamp comprises a body of an extruded profile. The body comprises at least one section with a mirrored surface and at least a lens section which allows exiting of light from the body. At least one LED preferably having a LED lens is provided at the inner side of the body. This combination of optical systems results in an asymmetric beam pattern from the source.