“The meaty mushrooms act as a canvas for any flavor you’d like to incorporate,” says the culinary star. “Creamed spinach gives it a real steakhouse vibe.”
Rachael Ray’s Portobello Burger with Creamed Spinach
1 tbsp. unsalted butter
¼ cup plus 1 tbsp. extra-virgin olive oil, divided
1 large shallot, minced
1 garlic clove, minced
1½ tbsp. all-purpose flour
¾ cup whole milk
1 (9-oz.) pkg. frozen chopped spinach, thawed and wrung out in a kitchen towel
Pinch of ground nutmeg
¾ tsp. kosher salt, divided, plus more to taste
3/8 tsp. black pepper, divided, plus more to taste
2 oz. (¼ cup) Parmigiano-Reggiano cheese, shredded
2 tbsp. Worcestershire sauce
2 tbsp. balsamic vinegar
2 tbsp. finely chopped fresh rosemary
4 (3-oz.) portobello mushroom caps, brushed clean with a damp towel, gills removed
½ lb. fresh mozzarella cheese, thinly sliced
4 crusty rolls
Thinly sliced red onion, for garnish
1. Heat butter and 1 tablespoon oil in a medium skillet over medium high until melted. Add shallot and garlic; cook, stirring often, until softened, about 2 minutes. Sprinkle with flour; cook, stirring constantly, until smooth, about 30 seconds. Gradually whisk in milk. Bring to a simmer, stirring occasionally. Stir in nutmeg, ½ teaspoon salt and ¼ teaspoon pepper, and add spinach. Cook, stirring often, until heated through, about 2 minutes. Stir in Parmigiano-Reggiano. Reduce heat to low; cover, and stir occasionally while making burgers.
2. Combine Worcestershire sauce, vinegar, rosemary and remaining ¼ cup oil in a large ziplock bag. Add portobello caps; seal bag, and tilt to coat.
3. Preheat grill to medium high. Shake marinade off portobellos; discard marinade. Cook portobellos, grill side down, until charred, 4 to 5 minutes. Turn portobellos, and sprinkle with remaining ¼ teaspoon salt and 1/8 teaspoon pepper. Top with mozzarella. Cook until mushrooms are tender, 4 to 5 minutes. Remove from heat, and tent burgers loosely with foil. Let stand until cheese melts, 1 to 2 minutes.
4. Place 1 portobello cap on bottom half of each roll. Top each with about ¼ cup creamed spinach and a few onion slices. Cover with top halves of rolls.
The creamed spinach recipe can be made a day ahead and then chilled in the fridge. Reheat the spinach in a heatproof skillet on the grill as the burgers are cooking.
Active time: 30 minutes
Total time: 40 minutes
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