I consider this a pan sandwich recipe. They fry a bunch of mushrooms and green onions in a hot oven as the main ingredients. And you whip a plain poblano yogurt while these are roasting. Stack them all high on hearty slices of well-toasted bread and you're done.
The poblano yogurt is a key component here, but I totally understand if you want to skip it due to time, lack of poblanos, or anti-chile. No problem, almost any flavor-enhancing yogurt slather will do in its place. You can simply crush a clove of garlic with a pinch of salt into a paste and stir it in your favorite yogurt – delicious too. Or, beat a tablespoon of harissa paste into your yogurt.