Line a baking sheet with tinfoil and lay 3 poblanos on it. Roast in the oven preheated to 400 F for about 40 minutes, flipping over once as they roast. Remove from oven once done and let them cool before removing skins.
While the poblanos are roasting, chop the potatoes and shallot.
In a large pot, add the shallot to 1 tablespoon of olive oil. Saute over medium heat until soft and translucent and slightly browned.
Once the shallots are done, add the flour in small increments, mixing with the shallots. Add 5 cups of broth and the chopped potatoes to the pot. Turn the heat up just above medium. Slowly stir in the heavy cream and spices.
The poblanos should be cooled down enough to remove the skins and dice. Poblanos have little spice to them. To lower the spiciness even more, be sure to remove the seeds.
Add the poblano and corn. Using a stick blender, blend up a bit of the soup. This, along with the flour, will help thicken the soup. You can also use a regular blender if that's what you have. Take out a cup of soup and blend it before returning it to the pot. Simmer over medium heat for 20 minutes, or until potatoes are fork tender.Be very careful when blending hot liquids, especially with the stick blender, so it doesn't splash on you. Top with cheese, sour cream, cilantro, crumbled bacon, and scallions if desired.