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Provençal tuna sandwich - Saveur suggests revitalizing your standard tuna mayonnaise sandwich with Provençal-inspired ingredients.

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Provençal tuna sandwich - Mix good quality tinned tuna with minced artichoke hearts, pitted niçoise olives, olive oil, paprika, and salt.

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Provençal tuna sandwich - Serve on a fresh roll with roasted red pepper, a sliced boiled egg, and lettuce.

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Use good bread - Serious Eats shares a guide to making a better sandwich that reinforces that the start to any good sandwich is decent bread.

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Or improve mediocre bread - It also suggests that if you only have sub-par bread at hand, you can vastly improve a sandwich by toasting or griddling the bread with some butter.

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Chickpea salad - This vegan sandwich recipe from Oh She Glows will make you forget all about tuna.

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Chickpea salad - In a large bowl, mash a tin of chickpeas with a potato masher until flaky. Stir in finely chopped celery, green onions, pickles, bell peppers, vegan mayonnaise, and garlic to taste.

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Chickpea salad - Add mustard, dill, lemon juice, salt, and pepper to taste. Use as a sandwich filler, side dish, or nutritious topping for a baked potato.

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Condiments - Use good butter and condiments to improve flavor and add moisture. Nobody likes a dry sandwich!

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Condiments - Oily condiments such as mayonnaise also provide a barrier to the water in vegetables, helping to prevent a soggy sandwich. Consider adding garlic, sriracha, or spices to mayonnaise to make a more exciting lunch.

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Smoked eel with onion pickle - Great British Chefs suggests this recipe from Jeremy Lee. Sourdough is filled with smoked eel, horseradish cream and Dijon mustard, and then toasted. Homemade red onion pickle takes it to the next level.

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Smoked eel with onion pickle - Make the onion pickle by gently warming sugar and vinegar before adding 1/4 of a sliced red onion and setting aside to steep off the heat.

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Smoked eel with onion pickle - Grill a slice of sourdough in a griddle or frying pan over a medium heat and slice the eel fillet into three even pieces.

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Smoked eel with onion pickle - Spread the toasted side of the bread with butter and a little Dijon mustard. Slice the bread in half and top one half with the eel pieces followed by horseradish cream. Place the other half on top, toasted side down, and return the sandwich to the pan.

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Smoked eel with onion pickle - Grill the sandwich on one side until brown, then flip and grill until golden and toasted. Drain the pickle and serve with the sandwich.

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Use quality vegetables - Using high-quality vegetables adds flavor. It's a good idea to add slaws, pickles, and marinated vegetables for brightness and contrast to otherwise regular sandwiches.

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Season your sandwich - Sea salt, black pepper, and olive oil are obvious seasonings that can improve the flavor of sandwiches and individual ingredients, but also consider herbs and spices such as paprika and chili.

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Tofu banh mi - Take some inspiration from Vietnam. Banh mi are baguettes filled with meat or tofu and coriander, cucumber, and pickled vegetables. This flavorful recipe from Slate is worth the preparation time.

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Tofu banh mi - At least one day before you plan to make the sandwiches, cut extra-firm tofu into slices. Freeze overnight and then thaw in the fridge.

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Tofu banh mi - Combine a shredded carrot, with two tablespoons of rice vinegar, one tablespoon of sugar, and a large pinch of salt. Cover and refrigerate. Whisk together a little butter or mayonnaise with sriracha.

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Tofu banh mi - Mix a tablespoon of water with a little sugar over a medium heat. When the sugar is mostly melted and golden brown, drizzle in soy sauce or fish sauce, then add a thinly sliced onion. Cook, stirring often, until the onion is tender and then add the thawed tofu and some black pepper.

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Tofu banh mi - Stir in another tablespoon of rice vinegar and remove from the heat. Drain the carrot mixture. Split a fresh baguette horizontally and discard some of the inside to make more room for the fillings.

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Tofu banh mi - Spread the butter or mayonnaise mixture on the bottom half of the baguette, and top with the tofu and carrot. Add chopped cilantro, cucumber, and jalapeños to taste. Close the sandwich with the top half of the baguette and enjoy!

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Tomato sandwich - Saveur recommends keeping it simple with sliced tomato and mayonnaise on toasted bread. The key is to use fresh, high-quality tomatoes and bread, and to season with sea salt, fresh pepper, and a tiny sprinkle of sugar.

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Temperature - It's best to warm up your protein, even for a cold sandwich. Warming meat or tofu and bringing other ingredients to room temperature will improve the flavor. Avoid keeping your lunch in the fridge!

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Roasted aubergine with pepper and beans - Real Simple provides a recipe for a nutrition-packed vegan sandwich that will make you look forward to lunch.

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Roasted aubergine with pepper and beans - Cut an aubergine into slices, brush with olive oil, and place on a baking sheet. Season with cayenne pepper and sea salt and bake in a medium oven for around 20 minutes, turning once and removing when soft and browned. If you want to make your own roasted red peppers, you can add these to the baking sheet too. Otherwise, buy a jar of roasted peppers in oil.

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Roasted aubergine with pepper and beans - While the aubergine bakes, mash half a tin of white kidney beans with a tablespoon of tahini and a tablespoon of olive oil. Add crushed garlic, lemon juice, salt, and ground black pepper to taste. Play with the amounts until you get a paste of a consistency you like.

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Roasted aubergine with pepper and beans -

Spread the bean mixture on foccacia and top with the aubergine, roasted red peppers, and romaine lettuce.

See also: 60 yummy recipe ideas and serving suggestions using citrus fruits

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