Mashed Potatoes

Another vote for low-sodium chicken broth, but lose the olive oil. Instead, reserve the cooking liquid (the broth, which will now have some potato starch in it) and use that.

Water works. You can add all kinds of things to improve the flavor (see above) but when you're making substitutions you need to think about consistency. In other words, don't try to substitute oil or eggs for milk in a recipe, it won't work. Substituting water for milk, however, does work. The added water (use the cooking water) will give the taters the right texture, then add whatever you like to add flavor.

I recently discovered that my mom has been making the Thanksgiving mashed potatoes with a few globs of mayonnaise instead of butter for years. It's good. Creamy. Of course, if your friend is a vegan rather than lactose-intolerant, the eggs in the mayo will be a problem. I don't think soy mayo would cut it.

Adding to what Secret Life of Gravy said, if you have a Garlic roaster, which is a little terra-cotta hut for the garlic, you can "roast" the garlic in the microwave in one minute. (you do the same prep.; removing the top of the bulb, olive oil, salt, &c.) Sometimes I'll eat garlic smashed potatoes all by themselves. I'm crazy like that.

Garlic Smashed Potatoes One head of garlic 2 lbs yukon gold potatoes, cleaned and quartered 1 TB salt 3 to 4 TB Olive Oil Roast the garlic by cutting off the top, brushing with olive oil, wrapping in foil and baking for 40 minutes at 400 degrees. Meanwhile put the potatoes in cold water, add salt and bring to a boil. Boil 20 minutes. Strain the potatoes and put back in the pot. Squeeze out the roasted garlic and smash with potatoes. Add the oil and smash until desired consistency. You may want to thin with a little cooking water or broth.

I second Yukon Golds. Make sure not to make the mistake I did once at Thanksgiving: I was trying to be calorie conscious and heard that mashed potatoes made with chicken broth were a delicious and lower-calorie way to prepare them. But in my literal mind, I thought this meant to boil them in chicken broth, rather than boil them in water and use chicken broth as a thinner/flavoring agent when mashing. When you boil Yukon Gold potatoes in a pot full of chicken broth you end up with eight pounds of wallpaper paste. Tasty. Lower Calorie. Suspiciously stringy -- think deep dish pizza. I have no idea what sort of freakish chemistry happened there, but if you decide to go the chicken broth route -- boil in water, drain, mash with chicken broth, serve and most importantly, enjoy.

I'll second smich's Earth Balance recommendation; the stuff is incredibly good. My brother-in-law who has high cholesterol turned me on to it. I adore butter but this is the next best thing. Trader Joe's carries it.

I've boiled potatoes with sprigs of rosemary in the water, and it gives the mashed potatoes this fantastic herby flavour...

Thanks everyone!!! I don't know much about the restrictions or the reasons but I'm going to stay away from milk and butter, even the lactose-free kind, to be safe. Will try the chicken broth, dulse (very interesting!), olivio, and peeling/different potatoes (will look for yukon golds tonite.) Good thing I like potatoes. Garlic and horseradish are already in my recipe anyway :) Now, can I mark all these answers as best?