Preheat the broiler.
Place the poblanos on a baking sheet and char under the broiler, flipping as each side blackens, until the entire pepper is blackened, about 3 minutes on each side. Heads up: leave the oven door open a crack to allow steam to escape as peppers cook. Peppers may also be charred over an open flame on a gas top stove. While the charred peppers are still hot, transfer them to a large bowl and over with plastic wrap. Let the peppers steam until the skin is loose and peppers can be handled, about 5 minutes. Peel the skin from the peppers and cut each one open with a single slice from the stem to the base. Carefully scoop the seeds out of the pepper, maintaining the pepper's entire shape. Reserve the peppers.