Wrap the potatoes in foil and bake at 350 degrees until tender. While they're still hot, pass the potatoes through a potato ricer. Or mash with a potato masher until fine.
In the meantime, roast poblanos over open flame on your gas stove top. One by one, simply place the poblanos directly on the grates turning them often to get the black and blistered.
When the poblanos are cool enough to handle, make a slit down the center of each pepper. Remove some of the seeds and a little bit of the veins if you'd like. This will make the peppers less spicy with heat. I don't remove much of the blackened skin, because this is where the smoky flavor lies. If you must remove skin, do so with your hands. Don't rinse the peppers under water. You're rinsing away flavor.
When the potatoes are at room temperature. Mix in the goat cheese. With clean hands, mix well.
Add the salsa and the Sambal Oelek. Mix well. Taste and adjust for flavor. Add Salt and Pepper to taste.
With a spoon, stuff each poblano with a good amount of the potato mixture. Place each stuffed pepper on a sheet pan. Place a pat of butter on top of the mashed potatoes.
Bake 350 degrees for 30 minutes. If you'd like them browned, finish them under the broiler for just a minute.