Ingredients

2 poblano chiles

4 jumbo portobello mushrooms (about 6 ounces each)

3 tbsp. plus 1 teaspoon extra-virgin olive oil

Salt and freshly ground black pepper

c. finely chopped onion

1 c. baby spinach

1/2 c. cooked rice

1/4 c. shredded sharp Cheddar cheese

2 tbsp. coarsely chopped cilantro

Preparation

Step 1Light a grill or preheat the broiler. Roast the poblanos over the grill or under the broiler, turning, until blackened, 3 to 4 minutes. Transfer to a bowl, cover with plastic wrap and let cool. Peel, core and seed the poblanos then finely chop them.Step 2Brush the portobello mushrooms with 3 tablespoons of the olive oil and season with salt and pepper. Grill or broil the mushrooms over high heat, turning, until softened, 10 to 12 minutes. Transfer to a plate, stem side down; let drain and cool.Step 3Meanwhile, in a medium skillet, heat the remaining 1 teaspoon of olive oil. Add the onion and cook over moderate heat until softened, about 6 minutes. Add the baby spinach and cook until wilted, about 1 minute. Transfer the spinach to a sieve and press out the liquid. In a bowl, mix the spinach with the rice, cheese, cilantro and poblanos. Season with salt and pepper.Step 4Preheat the oven to 325°F. Season the mushroom caps with salt and pepper. Spoon the rice mixture into the mushrooms, mounding it slightly. Transfer the mushrooms to a baking dish and bake for about 20 minutes, or until the cheese is melted and the top is lightly browned. Serve warm or at room temperature.Step 5Make Ahead: The cooked stuffed mushrooms can be refrigerated overnight. Bring to room temperature, cover and bake in a 325°F oven for about 20 minutes, or until they are heated through.