1. peel sweet potatoes, then dice into 1/2-1 inch cubes. This is best done with a sharp chef’s knife, as sweet potatoes can be quite hard. 
2. Place sweet potatoes in a large pan, and cover with water.
3. Heat to a boil, and boil until completely tender about 10-15 minutes.
4. Remove from heat, and drain sweet potatoes
5. Place back in pan, and mash with a potato masher. I find that with all potatoes (sweet and white), if you really want to mash all the lumps out, it’s best to do it before you add milk and butter. It’s a lot harder to get those lumps once those are added. 
6. Add butter, milk, maple syrup, salt, and cinnamon, and mash until smooth and well mixed. 
7. Serve as desired. 

Note: see “how to make mashed sweet potatoes” section above recipe card for instructions on using baked sweet potatoes, and other variations.