- Preheat oven to 375°F and grease muffin tin with butter or spray. 
- If needed, make mashed potatoes and let them cool to warm. 
- Combine mashed potatoes, sour cream, cheese, eggs, melted butter, and seasonings in a large bowl. 
- Fold in half of the bacon and most of the chives. 
- Scoop mixture into muffin tin, about ¾ full, and create a small indent on top. 
- Sprinkle with remaining cheese and bacon; press gently. 
- Bake for 25–30 minutes until golden and edges pull away. 
- Let cool 5 minutes, then remove gently and garnish with chives.