Preheat oven to 350.

Heat oil in a large skillet and sauté the spinach until wilted. Transfer to a large bowl and mix in the next 5 ingredients; season with salt and pepper.

Cut a slit along the side of the poblanos and remove the seeds and ribs. Fill the peppers evenly with the spinach mixture.

Roast the peppers on a greased baking sheet until peppers are soft and filling is bubbly; about 30 minutes.