I think I've come pretty close. Warning though, if you don't like spicy foods, you should not make this. I mean, hello, poblano peppers. A soup of hot peppers. If you love chile rellenos and don't think they're too hot, then this is for you.
I can't help it, I always shrug when I seed hot peppers. And then I do something stupid like rub my eye and spend the next two hours sobbing into a tea towel. Ha ha. If you happen to get a burn from hot peppers, soak it in milk. Instant relief. (I always tells visitors to drink a glass of milk when they go out for Tex Mex with me and have sensitive palates. Mmmm, milk.)
I might make a few changes (like adding a few cloves of roasted garlic, but no more than 2 because it could overpower the pepper flavor) and see how that affects the outcome. This was pretty dark green and not the lovely emerald of the restaurant's soup, but they may have put something else in to get that color, IDK.
Cream of Poblano Soup 6 C of soup or 3-4 main course servings
1 pat of butter (you determine the amount, I went on the scant side)
4 - 5 poblanos, roasted, skinned, unseeded, diced
1 small yellow onion, diced
2 TBSP Masa flour (if you don't have access, try 1 TBSP flour + 1 TBSP cornmeal. That'll be kinda close)
2 C water
2 C chicken stock
3/4 C cream or half and half or whole milk, whichever you dig most
Queso fresco and tortillas for serving (could sub in Monterrey Jack for queso fresco, but if you can get it, go for the fresco.)
Heat oven to HIGH BROIL, and put poblanos on a baking sheet right up under the heating unit. You want them to char a bit. Feel free to flip, but it isn't necessary. Pull out from oven and lay a tea towel over them to steam and cool down so you can handle them. Peel off skin, cut off stem and pull out ALL SEEDS (guys, I can't stress that enough) and the veins to which they're attached. Roughly dice.
Heat a large pot with the butter, toss in the onion and stir to coat. Sweat the onions, then add in the peppers, stir. Cook about 5 minutes, stirring occasionally, then sprinkle the masa over the veggies. Stir to coat for about a minute, then stir in the liquids. Bring to a simmer and cook for about 30 minutes, or until everything is softened and the liquid has reduced a bit.
Use a submersible blender or ladle out the veggies and a few splashes of stock and blend in a food processor or blender until smooth, add back to liquid and stir to combine. Remove from heat, add in the cream (slowly and stirring constantly so it doesn't curdle) and allow to heat through while you get the bowls out.
Ladle soup into bowls, top with a generous pinch of queso fresco (or Monterrey Jack if you can't find it) and some cheeps, om nom nom, chapstick the lips, suck in air, then om nom and repeat.
It's HOT. But it's the kind of heat that goes away, it doesn't linger and burn like a jalapeño or Sriracha sauce. If you can get your hands on Hatch chiles, oh, man, that's the best here. (I had half Hatch in my batch, I saved some in the freezer.)
I have too much to do today which means I should not be contemplating Fallout: New Vegas FANFIC for chrissake. I'm frowning at my brain, too, guys, I don't even know any more. I also didn't need to spend a half hour ironing my PILLOWCASES. I think I'm having a mental breakdown, quick, someone send chocolate and a pool boy!