Peel the waxy skin from the rutabagas with a vegetable peeler.
Then cut the rutabaga's into medium sized cubes (around 1 inch or 2 cm), and add to a large pot.
Add enough cold water to the pot to cover the rutabaga cubes by about an inch (2 cm) or so of water. Then add 1 tablespoon of salt and stir into the water until dissolved.
Then place the pot on the stove and bring to a boil on high heat.
Once boiling, reduce heat and simmer for around 30 minutes, or until fork tender.
Strain the rutabaga's in a colander and place in a large mixing bowl.
Add the butter along with one teaspoon of salt and pepper to the rutabagas. Then mash with a masher, mixing the butter, salt, and pepper into the rutabagas.
After using a masher, I then like to use an immersion blender to make the rutabagas nice and creamy.
Add salt and pepper to taste, serve, and enjoy!