Roast poblanos and green onions in the smoke box with the fire.. The green onions will cook quickly and are ok to have a little char. Completely char the skin of the poblanos. Place both in a bowl and cover with plastic wrap. Leave to steam and cool.
When the poblanos have cooled enough to handle, place green onions on a cutting board and begin removing the skin, stems, and seeds from poblanos.
Finely mince the poblanos and the green onions. Combine with the rest of the ingredients. Refrigerate until ready for use.