Heat a large pot on medium. Add the coconut oil, salt and chopped onion, and cook 4-5 minutes until soft. Add the 5 cups of broth and 2 cups of split peas. Bring to a boil, then cover for 45 minutes until peas are al dente.
Ladle 1/2 the soup onto a bowl, and blend the rest with an immersion blender, or pour into your regular blender. Combine both back into pot, stir in cream, add a squeeze of lemon and more salt if needed. Can be served over brown rice or quinoa for a heartier meal.