Caramelized Onion Grilled Cheese Sandwiches With Miso Butter

Serves 2.

Note: These indulgent sandwiches get a nice tang from whole-grain mustard and a big hit of umami from the miso and the caramelized onions. Grilled cheese for dinner: Why not? Adapted from "Umami Bomb: 75 Vegetarian Recipes That Explode With Flavor," by Raquel Pelzel.

• 1 tbsp. extra-virgin olive oil

• 1 large yellow onion (1 lb.), thinly sliced

• 1/8 tsp. kosher salt

• 1 tbsp. rice vinegar, preferably unseasoned

• 3 tbsp. unsalted butter, at room temperature (or substitute vegan butter, such as Earth Balance), divided

• 2 tsp. white or dark miso paste

• 1 tbsp. whole-grain mustard

• 4 slices good-quality sandwich bread

• 4 oz. (1 c.) grated Gruyère cheese (or substitute vegan shredded cheese, such as Violife or Daiya)

• Cornichons (aka gherkins), for serving, optional

Directions

In a large skillet over medium-high heat, heat the oil until shimmering. Add the onion and salt and cook, stirring often, until the onions start to soften and brown, 5 to 6 minutes. Reduce the heat to medium-low and cook, stirring occasionally, until the onions are deeply browned and sticky, 30 to 45 minutes. Stir in the vinegar. Transfer the onions to a small bowl.

In a small bowl, mix 1 tablespoon butter with the miso paste and mustard. Spread one side of each bread slice with the miso butter. Spread the other sides with the remaining 2 tablespoons butter.

Return the skillet to medium-low heat. Place 2 of the bread slices, plain-buttered-side down, in the skillet. Divide the cheese and onions evenly between them and top with the other bread slices, plain-buttered-side up. (You want the miso butter on the inside of the sandwiches.) Cook until the bread is golden brown, 5 to 7 minutes. (Resist the urge to press the sandwich with a spatula.)

Flip the sandwiches over and cook on the other side until the bread is golden brown and the cheese is melted, 5 to 7 minutes. Transfer to plates and serve with pickles, if desired.

Nutrition information per serving:

Calories620Fat45 gSodium960 mg

Carbohydrates33 gSaturated fat24 gTotal sugars7 g

Protein22 gCholesterol105 mgDietary fiber2 g