Sardine, Avocado & Pickled-Onion Tostadas with Pepita Salsa Verde

Why it works

Sardines are one of the richest whole-food sources of DHA and EPA omega-3s that build neuronal membranes, and they bring vitamin B12 needed for myelin and homocysteine metabolism. Avocado contributes monounsaturated fat and folate, cilantro and tomatillo add polyphenols and vitamin C, and pumpkin seeds supply magnesium and zinc that act as cofactors in neurotransmission, while the corn tostada keeps it naturally gluten-free.

Ingredients

• 4 corn tortillas (6-inch)
• 2 tins (each 3.75 oz / 106 g) sardines in olive oil, drained
• 1 ripe avocado
• 4 tomatillos, husked and rinsed
• 1/4 cup (35 g) raw pepitas (pumpkin seeds)
• 1/2 cup (15 g) fresh cilantro leaves and tender stems
• 1 jalapeno, stemmed (seeded for less heat)
• 1 small red onion, thinly sliced
• 3 tbsp lime juice, divided
• 1 tbsp plus 1 tsp extra-virgin olive oil
• 1 small garlic clove
• 1/2 tsp fine sea salt, plus more to taste

Method

1. Quick-pickle the onion: toss the sliced red onion with 2 tbsp lime juice and a pinch of salt and set aside to soften while you work.
2. Toast the pepitas in a dry skillet over medium heat for 2-3 minutes until they pop and smell nutty; set most aside for garnish.
3. Make the tostadas: brush the tortillas lightly with 1 tsp olive oil and bake at 400F (205C) for 6-8 minutes, or toast in the dry skillet, until crisp.
4. Blend the tomatillos, jalapeno, cilantro, garlic, half the toasted pepitas, 1 tbsp lime juice, 1 tbsp olive oil, and 1/2 tsp salt into a chunky salsa verde; adjust salt to taste.
5. Mash the avocado with a pinch of salt and spread over the crisp tostadas.
6. Top each with sardines, a spoonful of salsa verde, a tangle of pickled onion, and a scatter of the reserved pepitas; serve with the extra salsa on the side.