Many mashed potato recipes use butter and cream or milk as basic flavor-building blocks. This doesn't mean, however, that tasty dairy-free mashed potatoes are out of reach. With a few judicious substitutions, you can prepare a bowl of flavorful mashed potatoes suitable for serving to lactose-intolerant or vegan guests.
Moisten With Broth
The easiest way to add flavor and creaminess to a pot of mashed potatoes without leaning on dairy is to use stock to moisten the mash. Use chicken stock if you're simply sensitive to milk. For a dish suitable for serving to vegans, use a vegetable stock instead. Cook the potatoes in the stock before mashing for extra flavor. If you don't have stock on hand, save the cooking water and use it to moisten the potatoes instead.
Tasty Milk Substitutes
A variety of milk substitutes lend themselves to mashed potato recipes. Make sure that you use only unsweetened milk substitutes. Read the ingredients label closely, as most are sweetened unless otherwise noted. Try almond milk, soy milk, coconut milk, hemp milk or rice milk. Each adds its own subtle flavor to the finished dish; experiment to see which you like the best. Use milk alternatives as a straight substitute for dairy milk at a 1:1 ratio.
Instead of adding butter to mashed potatoes, incorporate olive oil to achieve a creamy texture. Olive oil, particularly extra-virgin oil, adds a particularly complementary flavor, but you can use just about any cooking oil. Experiment with corn, safflower, sunflower or grapeseed oils.
Other Flavorful Additions
A variety of other non-dairy ingredients keep mashed potatoes moist. Use margarine as a substitute for butter or a small amount of white wine to moisten the mash. Mash silken tofu with the potatoes for a moister finished dish. For a more exotic variation, add about 1/4 cup tahini per 2 pounds of potatoes to smooth the texture and add an interesting sesame flavor to the dish.