Tostadas de Atún (Mexican Tuna Tostadas with Chipotle Mayo)

Crisp corn tostadas piled with creamy tuna, avocado and quick pickled onion, a fast Mexican lunch with a smoky kick.

Made with Pickled red onions (cebollas encurtidas) and Tostadas and totopos (tortilla chips) and Homemade mayonnaise. Make a batch of the base first, then this takes minutes. Skip to the method

Nut free

Time20 min
LevelEasy
Costabout £2.04 a head
Oven180°C (160°C fan)

Cost is worked out from Aldi and Tesco shelf prices in October 2026. Your shop and brands will differ.

Estimated nutrition per serving

1310kcal
64.6gcarbs
8.5gof which sugars
110.9gfat
31.3gsaturates
14.3gprotein
10.1gfibre
2.5gsalt

A rough estimate worked out from the ingredients, for the serving size above. It is a guide only and not medical advice. If you count carbs or manage diabetes, check with your own tools and your care team.

4 servings

Ingredients

Tick what you need to buy. It goes on your shopping list.

80 mlgluten free mayonnaise
8gluten free tostadas
60 ggluten free pickled red onions
3tins of tuna in olive oil145 g each, drained
2avocadosripe, sliced
1jalapeñothinly sliced
1 tspchipotle pastegluten free
1limezest and juice
2 tbspfresh corianderchopped

Method

1
Flake the tuna into a bowl. Mix your ready made homemade mayonnaise (see the base recipe) with the chipotle paste, lime zest and half the lime juice.
2
Fold the chipotle mayonnaise through the tuna and season with salt. Taste, and add more chipotle for heat.
3
Toss the avocado slices in the rest of the lime juice to keep them green.
4
If your tostadas are not freshly made, warm them on a tray in a 180°C (160°C fan) oven for 3 minutes to crisp.
3 min
5
Spread a spoonful of tuna on each tostada, top with avocado, a few pickled red onions from your ready made batch (see the base recipe) and slices of jalapeño.
6
Scatter over the coriander and serve straight away, two tostadas each, before they soften.

Tips

Assemble at the table or just before eating. Tostadas turn soggy within 10 minutes of topping.
Use tuna in olive oil for the best flavour, and drain it very well so the mixture is not wet.
Tinned chipotle in adobo works in place of paste. Chop 1 pepper and stir in a little sauce.

Storing and freezing

Eat straight away. The tuna mixture keeps 1 day in the fridge in a covered pot, but top the tostadas fresh.

Questions

Can I use fresh tuna?

Yes. Sear a fresh tuna steak for 1 minute each side, rest, flake and fold through the mayonnaise. Tinned is more traditional for this street style snack.

How spicy is it?

Mild to medium, depending on the chipotle. Start with half a teaspoon of paste and add more to taste. Leave out the fresh jalapeño for less heat.

Is it gluten free?

Yes, when made with corn tostadas, gluten free chipotle paste and gluten free mayonnaise. Check labels on any shop bought tostadas.

More made with pickled red onions (cebollas encurtidas)

Main course

Pollo Pibil (Yucatecan Achiote Roast Chicken)

1 hr 40about £2.31 a head

DFEFNF

Main course

Pollo en Mole Rojo con Arroz (Chicken in Red Mole with Rice)

1 hrabout £1.41 a head

DFEFNF

BBQ & grill

Teriyaki Burgers with Grilled Pineapple and Pickled Red Onions

30 minabout £2.69 a head

DFEFNF

Vegetarian

Tacos de Hongos con Pipián Verde (Mushroom Green Pipian Tacos)

30 minabout £1.36 a head

GFDFEF

See every dish made with pickled red onions (cebollas encurtidas)

Double check before you cook. Recipes can contain mistakes. Any diet labels come from the ingredients as written in this recipe and are a guide, not a guarantee. Always check every ingredient and the packet label for allergens and cross contamination, and ask your doctor or dietitian what is right for you, especially with coeliac disease, diabetes or a serious allergy. This is not medical advice.