Preheat oven to 400 degrees Fahrenheit. Line a baking sheet with parchment paper.

Place potatoes on prepared baking sheet. Bake for 30–40 minutes, until tender. Set aside to cool.

Heat oil in a large frying pan over medium heat. Add onion; cook for about five minutes, until soft. Add garlic and carrot; sauté for an additional two to three minutes, until softened.

Add beef; cook, stirring to break up the meat, until meat is browned. Add ketchup and salt. Reduce heat to low; cook for about 10 minutes, until meat is cooked through. Set aside.

Meanwhile, prepare the potato skins. Cut each baked potato in half and scoop most of the potato flesh into a small bowl, leaving a small amount attached to the skin. (This will help the skin hold its shape.) Return potato skins to baking sheet.

Add oil, salt, pepper, and egg to reserved potatoes. Mash until smooth. Set aside.

Fill each potato skin with meat mixture, then spoon or pipe mashed potatoes over it. Repeat with remaining potato skins. Sprinkle paprika over potatoes.

Bake for about 20 minutes, until tops are golden.