Mashed potatoes, definitely.
Try throwing some garlic in the pot as the potatoes boil. When mashing, mash the garlic right along with the potatoes. Add some milk or cream, some butter, and salt and pepper to taste and there ya go...garlic mashed potatoes. Yummy!
Another favorite in my house is what we call Special Potatoes. Boil the potatoes just as you would for mashed pototoes. While the potatoes are boiling, cook a few strips of bacon until crisp. Let cool a few minutes and then crumble. Using the bacon grease, lightly saute some chopped green onions...just a few minutes until they are no longer raw. When the potatoes are done, mash them with cream, butter and salt and pepper or however you like to prepare them. Stir in some parmesan cheese, the crumbled bacon, and the green onions. Bake at 350 for 20-30 minutes. Top with more parm cheese and broil for a few minutes. This recipe is delicious, especially with a good steak! Good luck!