- 2 fresh poblano chiles
- 1 10-ounce bag cleaned spinach
- 3 tablespoons vegetable or olive oil
- 3 garlic cloves, peeled and halved
- 1 to 2 tablespoons masa harina (Mexican corn “flour” for making tortillas—look for it in most well-stocked groceries)
- 1 ½ cups milk, plus a little more if needed
- 4 4- to 5-ounce portions (1 to 1 ¼ pounds total) boneless, skinless salmon fillets (snapper, halibut and catfish are also good here)
- Salt and ground black pepper
- Roast the poblanos over an open flame or 4 inches below a broiler, turning regularly until blistered and blackened all over, 5 minutes for an open flame, 10 minutes for the broiler. Place in a bowl, cover with a kitchen towel, and let cool until handleable.
- Place the spinach in a microwaveable bowl, cover it with plastic wrap, poke a few holes in the top and microwave until completely wilted, usually about 2 minutes at full power. (If your spinach comes in a microwaveable bag, simply microwave it in the bag.) Uncover (or open the bag) and set aside.
- Turn the oven on to its lowest setting.
- Heat the oil in a very large (12-inch) skillet (preferably non-stick) over medium. Add the garlic and cook, stirring regularly, until soft and lightly browned, about 4 minutes. Using a slotted spoon, scoop the garlic into a blender. Set the skillet aside.
- Rub the blackened skin off the chiles and pull out the stem and seed pod. Rinse the chile flesh to remove bits of skin and seeds. Roughly chop and add to the blender, along with masa harina and milk. Blend until smooth.
- Return skillet to medium-high heat. Sprinkle the fish liberally with salt and pepper. Lay the fillets in the hot oil and cook until richly browned, about 2 minutes. Use a spatula to flip the fillets, then cook until the fish barely flakes when pressed firmly with a finger or back of a spoon (you want it slightly underdone), usually a couple of minutes longer for fish that’s about 1 inch thick. Using the spatula, transfer to an ovenproof plate and set in oven.
- With skillet still over medium-high, pour in the poblano mixture and whisk the mixture until it comes to a boil and thickens, about 1 minute. Reduce heat to medium-low and simmer for 5 minutes, stirring frequently, to blend the flavors. If the sauce has thickened past the consistency of a cream soup, whisk in a little more milk. Taste and season with salt, usually a generous ½ teaspoon. Add the spinach to the sauce and stir until the spinach is warm and well coated with the sauce.
- Divide the creamy spinach onto 4 plates. Top each portion with a piece of seared fish. (If it sounds more appealing to you, spoon the sauce over the fillets.) Serve without delay.