Peel and chop your potatoes into roughly 1 inch chunks. Place in a pot of water, bring to a boil and allow it to cook for about 20 minutes until able to easily pierce with a fork.
While the potatoes are boiling place your poblano over an open flame and get it nice and blistered. Place it in a bowl and cover with a plate.
Once potatoes are done drain them and add Tbsp. or butter mashing the potatoes. Remove the poblano from the bowl, remove the stem cut it length wise seed and peel. Dice the poblano and add it to the mashed potatoes.
In a pan/skillet add the remaining butter melt, and sauté your chopped mushrooms. Once nice and tender add into the potatoes salt and pepper to your taste and mix.
In a heavy bottomed pan heat about a half inch of vegetable oil. Place about 2 heaping spoon fulls of potato onto one of the tortillas and tightly roll them.
Add them into the heated oil and allow to cook for about a minute until a golden brown flip over and cook the other side for another minute.
Remove from oil place on a paper towel and serve.