I visited Panama for an agricultural trip about a decade ago where we focused on coffee agriculture and production. Coincidentally, there are some coffees that blend in beans or peanuts to mellow the flavor. This is usually done for cheaper coffees that use robusto beans instead of arabica. It’s also to relieve some of the acrid taste that can develop during the drying out process if the beans are dried around animal droppings.
If you’re interested in what a mellowed coffee would taste like, I think chock full of nuts is a brand you can try in the states.
Edit: ok so I did some more research and it appears that chock full o nuts likely no longer does this, they just have typical coffee nowadays. I’ll leave it to you other internet sleuths to find a brand that does.