Fill a large pot half way up with water. Place over high heat on stove and begin to bring to a boil. Cut peeled yams into 2 inch chunks and place in the water with 1 tsp salt. Boil until fork tender then drain in a colander.
Place hot yams into the bowl of a stand mixer. (You can also mash these by hand with a potato masher). Turn mixer on low and begin to mash yams. Add yogurt, cinnamon, nutmeg, syrup, and butter. Turn mixer to medium to whip yams into a creamier mixture for about 15 seconds. Return to low and add chicken (or vegetable) broth, then mix another 10 seconds. Taste for seasoning.
Place in a large bowl, drizzle with a little more maple syrup and a sprinkling of cinnamon.
Notes
Careful not to over mix the potatoes - they can turn gummy pretty easily. If you'd rather mash these with a potato masher, then mix in the ingredients, that's fine too.
Recipe by Eating Made Easy at https://eating-made-easy.com/thanksgiving-side-dish-3-ways-with-sweet-potatoes/