or you can just go with cowboy coffee. boil the grinds in water and pour out carefully.
I worked as a whitewater raft guide one summer when I was a teen. We cracked an egg and mixed it in along with the grounds when making the morning pot of coffee over the campfire. When it was done we poured a cup of cold water into the pot to sink the raft of grounds and solidified egg. The coffee came out grit-free and mellow. Apparently something in the egg counteracted the bitterness you usually get with over-boiled coffee.Yuk. Bitter and grainy.
Let me do a quick Google to see if my memory holds up:
Why You Should Crack an Egg Into Your Coffee Grounds
For a velvety cup without any hint of bitterness
www.eater.com