Gone are the days of mashed potatoes as a side in my house since discovering cauliflower can replace white potatoes pretty easily. They look pretty similar too. Start out with half a head of cauliflower and steam the cauliflower. I use my rice cooker and just use the "steam" setting but you can steam it however you normally do. Don't remove it until it's completley mushy.
Mash the cauliflower up really well in a bowl.
Add 2 chopped green onions
1 tablespoon butter/margarine
1 dash of salt (totally optional)
3 TABLESPOONS of chopped garlic
Then enjoy your potatoeless (is that a word?) guilt free mashed cauliflower!