Start by cutting the onion, poblano pepper, and red bell pepper into medium/small dice, use a mandolin if you have one. Add 3 Tbsp of butter to a medium-sized pot and melt, once melted add onion and sweat for a few minutes, then add the poblano and red bell pepper along with a pinch of salt. The salt helps the sweating process and releases the natural water.
Next, add the chipotle pepper and Rotel (add to taste) along with the flour and mix well. Once mixed add the cream of mushroom (you could use cream of chicken soup as well) then add 2 Cups of Chicken stock.
You may need a little more flour to thicken just right. The reason is all flours do not absorb the same.
Add all the season next, chili powder, garlic powder, cumin, oregano, black pepper. Taste and adjust your season, salt level etc. I added 5 Tbsp cream of corn to balance the flavors. Highly suggest you do as well.