1-First, in a bowl, whisk together 1 tablespoon lemon juice, 3 tablespoons olive oil, 2 tablespoons chopped fresh parsley, 1/2 teaspoon sugar, 1/2 teaspoon salt, 1 large or 2 small garlic cloves (pressed), and 2 teaspoons balsamic vinegar to make the marinade. This base infuses the mushrooms with a tangy, herbaceous kick that really brings out their natural taste.

2-Next, clean the 4 portobello mushroom tops with a damp paper towel and remove the stems to prepare them for stuffing. Brush the marinade evenly on both the top and bottom of each mushroom cap, then refrigerate for 30 minutes. This step is key for enhancing flavor and ensuring tender results.

3-Preheat the grill and oil the grates to prevent sticking, then place the mushroom caps gill-side down on the grill, cover, and cook over medium heat for 6 minutes. The grilling method keeps things juicy and adds a smoky note that food enthusiasts love. For variations, some readers share that trying similar techniques with fruits like in peach cobbler can inspire creative twists.

4-Flip the mushrooms so they are gill-side up, then fill each one with about 1/4 of the 1 1/2 to 2 cups fresh spinach leaves and 1 slice of cheese. Cover and grill for an additional 4 minutes, or until the cheese melts, the spinach wilts, and the mushrooms are tender. Be careful not to overcook to avoid excess juice, as shared in our tips section.

5-For sandwiches, slice and toast the 4 rolls on a buttered skillet, let them cool slightly, then spread a thin layer of mayonnaise on each slice. Top with the stuffed portobello mushrooms, sliced fresh tomato, and additional spinach if desired. Serve immediately for a satisfying meal that’s perfect for travelers or newlyweds on the go.