Preheat oven to 400°F.
Using a fork, pierce each sweet potato several times. Place on a lined baking sheet and bake for 30-45 minutes, or until cooked through.
Allow the potatoes to cool. Cut in half and scoop out the insides using a large soup spoon into a large bowl. Discard the skins.
Using a potato masher, mash the sweet potatoes.
Add the yogurt, honey, and cinnamon to the potatoes and mix until well combined.