Preheat oven to 300°F.
Place the potatoes in a medium saucepan on high heat with enough water to cover them. Cook 15 to 18 minutes, until soft. Drain in a colander; set aside. Meanwhile, wrap all the tortillas tightly together in foil and place in oven for 5 minutes. Place the saucepan back on low heat and add the butter and bacon. Stir until warm and sizzling, about 2 minutes; remove from heat. Add the potatoes, peas, thyme, half the scallions, and half the sour cream. Stir and mash with a potato masher or a wooden spoon. Season with the salt and pepper to taste. Remove the tortillas from oven and place 2 on each plate. Put 1/3 cup of the potato mixture on each tortilla and roll them as shown above. Top each with a spoonful of the remaining sour cream and sprinkle with the remaining scallions and a few grinds of black pepper to taste.