To make it butter-free you can use the potato water trick. Reserve 1 cup of potato water when you drain your cooked potatoes. Then slowly add some back in while you mash. You should see your mash become nice and creamy. To give it great flavor, add some additional sea salt and fresh herbs like oregano, thyme, or rosemary. Enjoy your butter-free mash! We have made butter-free creamy mashed potatoes many times, since we use vegan butter which contains cashews, to make it an allergy-friendly recipe for my mother-in-law we often use the potato water trick with great success. Just remember to add more spices to make up the flavor.