Bake the sweet potatoes:

Cup of Yum
1. Preheat oven to 400 degrees F, and line a baking sheet with foil. Wash and dry the sweet potatoes and prick the skins several times with a fork.
2. Place sweet potatoes on the baking sheet and bake for 1 hour, flipping at the halfway point. They're done when easily pierced with a knife. Let cool for about 20 minutes or until cool enough to handle. Alternatively, let cool completely, then refrigerate until ready to peel and proceed with the recipe.

Toast the pecans and saute the veggies:

1. Preheat a saute pan over low heat. Toast the pecans in the pan, stirring frequently, for about 5 minutes or until fragrant. Transfer pecans to a plate to cool. Once cool, roughly chop the nuts and set aside.
2. Return the saute pan to the stove and increase heat to medium. Cook the onion for about 5 minutes or until translucent, stirring occasionally. Add broth and garlic to the pan, and cook for 3 to 4 minutes. Add rosemary, sage, and black pepper, and cook until most of the broth has evaporated and the onions are softened. Remove from heat.

Assemble the mashed sweet potatoes:

1. Peel the sweet potatoes, discarding the skins, and place in a large bowl. (If potatoes were made in advance and are cold, warm them in the microwave or on the stovetop.) Add about ½ cup yogurt to the bowl, and use a potato masher or fork to mash the sweet potatoes. Add the onion mixture and salt, and stir to combine. Taste and add more yogurt, salt and pepper, as desired.
2. Transfer mashed sweet potatoes to a serving dish. Garnish with a swirl of plain yogurt and sprinkle with the chopped pecans. Serve warm.