• To prepare the sweetpotatoes for both the cupcakes and frosting, peel the two sweetpotatoes and chop into 1-inch cubes. Place in a pot and cover with water. Bring to a boil over high heat. Continue to cook for 13-15 minutes over high heat, until sweetpotatoes are tender. Drain and let cool for a few minutes, then puree in a food processor or blender.
• Meanwhile, preheat oven to 350F. Grease a 12-count cupcake tin, or line it with paper cupcake liners.
• Next, start to prepare the cupcakes. In a measuring cup, combine the milk and vinegar. Set aside for now.
• In a large mixing bowl, cream together the butter and sugar.
• Add the eggs, yogurt, vanilla, and ¾ cup of the cooked pureed sweetpotato. Stir until well combined.
• Add the whole wheat flour, cocoa powder, baking powder, and salt. Stir a couple times, then pour in the milk-vinegar mixture. Stir until combined.
• Portion the batter evenly into the wells of the cupcake tin. Bake at 350°F for 15-17 minutes, or until cooked through. Let cool fully in the pan.
• Meanwhile, prepare the frosting. Place the white chocolate chips in a microwave safe bowl. Heat in the microwave in 30-second intervals to melt the chocolate, stirring between each interval.
• When the white chocolate is melted, stir in the yogurt and ¾ cup of sweetpotato puree. Place in the fridge for an hour while you continue to wait for the cupcakes to cool.
• Frost the cupcakes immediately before serving. Enjoy!

Notes:

• Placing the frosting in the fridge for an hour will allow it to firm up into a pipeable texture. However, if you don’t mind a softer texture, you don’t have to wait that long.
• If you’d prefer to reduce the sugar content, you can use a granulated alternative sweetener like allulose in place of some or all the sugar in the cupcake. You can also use stevia-sweetened white chocolate chips in place of regular white chocolate chips in the frosting.
• Unfrosted cupcakes can be stored at room temperature in an airtight container for up to 2-3 days. However, because the frosting contains yogurt, it shouldn’t be left out for more than 2 hours. You can store the frosting separately in the refrigerator and add to the cupcakes immediately before serving.