I'm writing a scene where the skin tone of an adult person of color (POC) is brought up in conversation. The POC has the nickname "Ghost" and another character asks if it's ironic like "Tiny" etc. (we later find out it's because of certain supernatural abilities.) The character who brings up the topic is made out to be an ass and has been trying to get a rise out of Ghost. The scene serves to show that Ghost is very self-controlled.
I wanted Ghost to think back to when he was a child, when another POC bullied him for having darker skin. Upset, Ghost runs to his grandmother, who calms him and explains that sometimes people just want to pick a fight and it can be over the stupidest things and that we're all human and your skin tone makes you no better or worse than anyone else.
I was going to try use a coffee analogy, something like "Some people like it strong and black, while others like creamer and more sugar than you'd find in a cake, but it's all still coffee. Each way is no better or worse, and you wouldn't fight with someone over how they take it, right? It's just the way they like it." And then I was going to end on something like "Me, I like my coffee good and strong, just ask your grandfather" ... which would make Ghost smile, as it was something he didn't quite understand at the time, but as an adult reminds him of his grandmother's humour.
But... the coffee analogy suggests preference. I don't want it read that I'm saying it's fine to like or dislike a person based on skin colour. I'm also wary of coffee after reading some articles on coffee/chocolate being problematic to use due to links with slavery and plantation crops.
Question: How should I approach writing a scene where the POC grandmother explains to the bullied POC young child that having dark skin isn't a bad or good thing?
For context: I'm a white male. The work is a fantasy novel set at the start of this decade. I'm quite happy with the way the Ghost character has been written in the rest of the book, after this chapter there is a severe lack of humans and race is never brought up again. I chose to make one of the main characters a POC because the rest of the limited cast of humans were white.