Writing the other involves creating characters who differ from us (ethnicity, gender, sexual preference, age, personal philosophy, etc). When writers don’t take the time to research and think this through, it can come off artificial and supports stereotypes rather than contributing to the work’s diversity.
In written works, skin color is overvalued as a difference, and tends to be described in great detail when the character isn’t white (socially emphasized as the norm or primary color in the US).
Comparing the skin of people of color with food (she had a cafe au lait complexion, her dark chocolate hand, etc) can be a way of othering the characters, making them less human than the characters who don’t get compared to food. Are they people or something to consume? This method of description is almost never used with white characters.
She stood in the sun, her cheeks like silken tofu, as she waited for her Uber.
Her hand, the rich color of peeled garlic held him back.
Mayonnaise boy quickly joined the group.
While it’s true some writers will describe white characters as having creamy or milky skin, it’s not the norm to even note white character’s colors, as they are seen as the default. The connotations are also very different when a person in a position of social power or privilege granted by skin color does this to someone who is often othered.
Including diversity in sensitive ways can contribute to the richness of a work, and should be encouraged. However writers need to plan to avoid the pitfalls and things that can go very wrong.