As many potatoes you wish to serve
Butter 
Milk
  1. Pre-heat the oven to 180C
  2. Bake the potatoes (approx. 50-60 minutes)
  3. Once the potatoes are hot, skin them and push them through a sieve
  4. Heat your butter and milk
  5. Soak the potatoes in warm butter and milk
  6. Put them back in a warm flame and work in more room temperature butter until they are rich & silky

Note: If you want them softer, add more warm milk.