Preheat oven to 375°F (190°C) and lightly grease a muffin tin or line with silicone muffin cups. Peel and shred the sweetpotato using a box grater. In a medium bowl, mix together the shredded sweetpotato, shredded cheese, and oregano. Evenly divide the sweetpotato mixture into each muffin cup, pressing it down gently to form a little base. Bake the sweetpotato mixture for 15 minutes, or until softened and slightly golden. Carefully remove the muffin tin from the oven and crack one egg directly into each muffin cup over the cooked sweetpotato base. Return to the oven and bake for another 10 minutes, or until the egg whites are set but the yolks are still slightly runny (or fully cooked, if you prefer). Let cool slightly before removing. Serve warm or store in an airtight container in the fridge for up to 4 days.