Charred Caprese Sandwich

1. **Prepare the mayonnaise mixture:** In a small bowl, combine 4 tablespoons of mayonnaise, 2 teaspoons of Dijon mustard, and 1 teaspoon of fresh lemon juice. Season with 1 teaspoon of kosher salt and set aside.

2. **Pickle the shallots:** In another small bowl, toss 1 thinly sliced large shallot and 1 finely grated garlic clove with 3 tablespoons of red wine vinegar. Season with a pinch of salt and let sit for 10 minutes. Drain, reserving the shallots and vinegar separately.

3. **Grill the bread:** Preheat a grill or grill pan over medium-high heat. Brush the cut sides of 1 baguette (split in half lengthwise) with 2 tablespoons of olive oil. Grill until lightly charred, about 2 minutes per side. Season with salt and let cool.

4. **Char the tomatoes:** Heat a large cast-iron skillet over medium-high heat. Toss 3 cups of cherry tomatoes with the remaining 2 tablespoons of olive oil. Cook, shaking the pan often, until the tomatoes are blistered and lightly charred, about 3 minutes. Add the tomatoes to the bowl with the reserved vinegar from the shallots. Season with salt and freshly ground black pepper to taste. Let cool slightly.

5. **Add herbs and zest:** Once the tomatoes have cooled slightly, add 1 cup of torn basil leaves, 0.5 cup of parsley leaves with tender stems, and 0.5 teaspoon of finely grated lemon zest to the tomato mixture. Toss gently to combine. Taste and adjust seasoning with salt and pepper as needed.

6. **Assemble the sandwich:** Spread the mayonnaise mixture evenly on both halves of the grilled baguette. Top with 4 ounces of torn fresh mozzarella, the charred tomato and herb mixture, and the pickled shallots. Sprinkle with crushed red pepper flakes to taste.

7. **Serve:** Close the sandwich, cut into desired portions, and serve immediately.

8. **Tips for best results:**

- Use fresh, ripe tomatoes for the best flavor.

- Don't skip the pickling step for the shallots; it adds a delightful tanginess.

- If you prefer a spicier kick, increase the amount of crushed red pepper flakes.

- For a vegan version, substitute the mayonnaise with a plant-based alternative and use vegan mozzarella.

- To make the sandwich gluten-free, use gluten-free bread.

- If fresh herbs are unavailable, dried herbs can be used, but adjust the quantities accordingly.

- For added richness, drizzle a bit of aged balsamic vinegar over the assembled sandwich before serving.

- If you don't have a grill, you can use a broiler or a stovetop grill pan.

- To prevent the bread from becoming soggy, serve the sandwich immediately after assembling.

- For a smoky flavor, consider grilling the mozzarella cheese briefly before adding it to the sandwich.

- If you prefer a milder flavor, reduce the amount of garlic in the shallot pickling mixture.

- For a more robust flavor, consider adding a layer of pesto sauce to the sandwich.

- To add a crunch, consider adding a layer of arugula or spinach leaves.

- For a heartier meal, serve the sandwich with a side of roasted vegetables or a light salad.

- To make the sandwich more filling, add slices of grilled chicken or turkey.

- For a tangy twist, add a few slices of pickled jalapeños.

- To enhance the flavor, consider toasting the sandwich after assembling.

- For a sweeter flavor, add a drizzle of honey to the mayonnaise mixture.

- To make the sandwich spicier, add a few slices of fresh jalapeño peppers.

- For a more savory flavor, add a sprinkle of grated Parmesan cheese on top.

- To make the sandwich more flavorful, marinate the tomatoes in the vinegar mixture for a longer period before assembling.

- For a more intense flavor, consider roasting the tomatoes before adding them to the sandwich.

- To make the sandwich more filling, add a layer of sliced avocado.

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