1. Preheat oven to 350 degrees.
2. Roast potatoes on a banking sheet until tender (approximately 1 hour).
3. When the potatoes are cool enough to touch, cut in half with serrated knife.
4. Using a melon baller, carefully remove potato guts. Run guts through a ricer and place into a mixing bowl. Place skins on a lightly greased baking sheet.
5. Preheat the broiler.
6. In saucepan, combine kale, leek, 2 tablespoons butter, nutmeg and bacon. Add pinch salt. Cover and cook over medium heat, stirring every 3 minutes, until leek and kale is soft (about 15 minutes).
7. Add milk to potatoes and mix well.
8. Add potato mixture to saucepan and combine with leek and kale.
9. Using spoon, fill potato skins with mashed potatoes and kale.
10. Place filled potato skins on baking sheet under the broiler until the tops begin to brown.
Remove from oven and serve warm.