Vegan Creamy Cheddar Mashed Potatoes

4 medium russet potatoes, peeled and sliced
1/2 cup nutritional yeast
1 cup soy milk
1 tsp yellow mustard
1/4 tsp garlic salt
2 tbsp vegan butter

Place potatoes in a pot and cover with water. Bring to a boil and cook until tender. In a small sauce pan over medium heat,whisk together nutritional yeast and soy milk and simmer until thickened. Remove from heat and whisk in mustard and garlic salt. Pour soy milk mixture over potatoes, add butter, and whisk until creamy. If more cheddar flavor is desired, sprinkle a few flakes of nutritional yeast to whisk in at the end. For a Thanksgiving spin, make rolls with tofurky deli slices and potatoes as the filling.