Melt ghee in a large saucepan over medium heat. Add in the fennel, sweet potatoes and garlic, and sauté for a few minutes.
Add in the bone broth, turmeric, sage, salt and pepper. Place the lid on the saucepan and leave to cook gently over medium-low heat for about 15-20 minutes, until the fennel and sweet potato are fork-tender and most of the liquid has been cooked off.
Add in the pancetta/bacon, if using, and gently stir for a couple of minutes until cooked.
Remove from the heat and serve, with a slotted spoon if necessary to drain excess liquid.
Bonus Tip: Leftovers are a dream with eggs!