That's a receipe probably not so different than the broth they did in the paleo era once they had access to fire.
You need a big leg bone from a mammal, a grassfed cow in our times. You can order it to your butcher but also in supermarkets, I bought this in WholeFood market NYC.
Some leafy vegetables, for instance I bought radishes ate them and kept the leaves, but it could be other left over vegetables
Heat water with bone at low temperature as long as the connective tissues around the bone are soft, put the greens for 15 minutes and that all you have your broth.
Don't add salt and try to accustom yourself to non salted broth and taste the true flavors of bone marrow, meat and greens. You can try to add pepper or other spices...
When you serve put a piece of bone marrow in the bowl.