Decide which meat you want to eat then make the potatoes to go with the meal.
For example, if you choose the pulled pork, you could make roasted potatoes. Cut the potatoes into uniform chunks, toss with oil and some garlic and onion powder, paprika and a dried herb such as rosemary or thyme. spread them out on a cookie sheet in a single layer and roast at 450º F for 30 or so minutes.
For the tuna, make parsley potatoes, boil the potatoes, toss with butter and chopped fresh parsley. Season with salt and pepper.
"If you want to make an apple pie from scratch, you must first create the universe." -Carl Sagan