M&M's color replaced by blue in 1995

TAN

This shade was originally introduced in 1941 as one of the first M&M's colors but later vanished from plain milk chocolate varieties. Think of a light brown hue often associated with coffee or sand.

In 1995, M&M's replaced one of their candy colors with blue after a fan vote. The color that got dropped was tan, which had been part of the mix since the 1940s. The clue is a straightforward reference to this real-world change, so the answer is simply the name of the removed color. No wordplay—just a bit of candy history.