1) Melt coconut oil in a 4 to 6-quart pot over medium-high heat.
2) Add leeks and cook until beginning to soften.
3) Add yams and cook for a couple of minutes. Add stock, just enough to cover the vegetables—you will add more later. Season with a pinch of salt and pepper.
4) Bring to a boil, lower to a simmer, and cook until leeks and yams are soft.
5) Using an immersion blender or regular blender, puree soup until smooth.
6) Top with chopped parsley