The Tunisian tuna sandwich, known as casse-croûte, is the ultimate street food in Tunisia: a baguette spread with harissa and filled with tuna, olives, hard-boiled egg, potatoes and mechouia, a salad of grilled peppers and tomatoes. You will find it in every little sandwich shop, from early morning until late at night.
I had one at the end of July 2026 at Royal Djerba in Phalsbourg, with tuna, olives, small grilled peppers, fries and a lot of harissa. Really a lot! It was delicious, the kind of sandwich that takes you on a trip without leaving Moselle.
Here is the traditional version, the one people make at home in Tunisia. The secret is a mechouia made with properly charred peppers: it brings a smoky taste that changes everything. As for the harissa, use as much as you dare!
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The recipe
Classic recipeThe traditional recipe for the dish, not the one from the restaurant where I tasted it.
Ingredients
Mechouia (grilled peppers)
- 6 long mild green peppers (or 3 green bell peppers)
- 2 tomatoes
- 1 garlic clove
- 1 tsp ground caraway
- 2 tbsp olive oil
- 1 tbsp lemon juice
- Salt
Filling
- 4 small baguettes (about 25 cm)
- 2 to 4 tbsp harissa
- 1 tbsp olive oil for the harissa
- 2 cans of tuna in oil (2 x 160 g)
- 300 g waxy potatoes
- 2 eggs
- 60 g pitted black or green olives
- 1 tbsp capers
- 1/2 lemon
- Olive oil for drizzling
Method
- Grill the peppers and tomatoes under the oven grill at 230 °C for 15 to 20 minutes, turning them halfway, until the skin is blackened and blistered. Place them in a covered bowl for 10 minutes so they sweat.
- Peel the peppers and tomatoes, then remove the seeds and stems from the peppers. Chop them finely with a knife together with the garlic, then add the caraway, olive oil, lemon juice and a pinch of salt. Your mechouia is ready.
- Meanwhile, cook the whole potatoes in salted water for about 20 minutes, until a knife goes through easily. Peel them and cut them into small cubes.
- Cook the eggs for 10 minutes in boiling water, cool them in cold water, peel them and slice them into rounds.
- Drain the tuna and flake it roughly with a fork, adding the juice of the half lemon.
- Slice the baguettes lengthwise without cutting all the way through and warm them for 3 minutes in the oven at 180 °C so they get crispy.
- Mix the harissa with the tablespoon of olive oil to loosen it, then spread it inside the baguettes. Add a generous layer of mechouia along the whole length.
- Fill with the potato cubes, tuna, egg slices, olives and capers. Drizzle with olive oil, close the sandwich pressing lightly and serve right away.
Tips and variations
- Like at Royal Djerba, you can tuck a few fries into the sandwich: it is very popular in Tunisia.
- The mechouia can be made the day before and keeps for 3 days in the fridge, in a jar topped with a little olive oil.
- No oven grill? Char the peppers directly over a gas flame or on the barbecue, the smoky taste will be even better.
- For a milder version, replace part of the harissa with tomato paste mixed with a little olive oil.
- You can add a few cubes of preserved lemon or a spoonful of Tunisian salad (tomato, cucumber, onion) for extra freshness.
Recipe shared for guidance only, adapt it to your equipment: times and temperatures may vary. Check for allergens (gluten, milk, eggs, fish, shellfish, nuts, sesame…) and make sure ingredients are fresh. Raw or undercooked fish, meat and eggs are not recommended for pregnant women, young children, elderly or vulnerable people. Take care with hot oil, flambéing and alcohol. I am not a health or nutrition professional.