Tostadas de Atún Sellado (Seared Tuna Tostadas)
Quickly seared tuna with chipotle and lime on crisp tostadas spread with guacamole.
Made with Classic guacamole and Tostadas and totopos (tortilla chips). Make a batch of the base first, then this takes minutes. Skip to the method
- Time25 min
- LevelEasy
- Costabout £1.38 a head
Cost is worked out from Aldi and Tesco shelf prices in October 2026. Your shop and brands will differ.
Ingredients
Tick what you need to buy. It goes on your shopping list.
Method
- 1
Mix the chipotle with the lime juice and 1 teaspoon of the oil in a small bowl. Rub half of it over the tuna steaks.
- 2
Heat a frying pan until very hot. Add the rest of the oil and sear the tuna for 1 to 2 minutes per side. The centre should stay pink; cook longer if you prefer.
3 min - 3
Rest for 3 minutes, then slice thinly across the grain.
3 min - 4
Quickly rinse the sliced red onion under cold water, drain, and mix with the coriander.
- 5
Spread each tostada (see the base recipe) with your ready made classic guacamole (see the base recipe). Top with sliced tuna, onion and a few drops of the remaining chipotle lime mix.
- 6
Scatter over the sesame seeds and serve at once.
Tips
- Pat the tuna dry before it goes in the pan. A dry steak sears and a wet one steams.
- Do not move the steak while it sears. Let it brown for the full time before turning.
- Serve straight after building. The tostadas soften after about 10 minutes.
- Check that the tuna is fresh and described as suitable for rare cooking. Cook fully if you are pregnant or serving people with weak immunity.
Storing and freezing
Eat straight away. Cooked tuna keeps in the fridge for 1 day; do not freeze assembled tostadas.
Questions
Can I use tinned tuna?
Yes. Mix drained tinned tuna with the chipotle lime mix and pile onto the tostadas. It is a very popular Mexican snack, tostadas de atún, in this simpler form.
Is the tuna safe to eat pink?
Fresh tuna is commonly eaten rare when it is very fresh, but it is not suitable for pregnant women, young children or anyone with a weakened immune system. Cook those servings through.
Are these tostadas gluten free?
Yes, as long as the tostadas are made from corn only. Check that your sesame seeds and chipotle tin have no added gluten.
More made with classic guacamole
Carne Asada a la Tampiqueña (Tampico Style Steak Plate)
NFEFTostadas de Nopales y Frijol Negro (Cactus and Black Bean Tostadas)
GFDFEFPanuchos Yucatecos (Yucatan Stuffed Fried Tortillas)
DFEFNFBurritos de Frijol y Queso (Bean and Cheese Burritos)
EFNFVDouble 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.