Step 1

Place the leek rounds into cold water. Agitate to separate the rings, then dry them.

Step 2

Heat oil in a large saucepan to 350°F.

Step 3

Fry tortillas until golden and firm, about 1 minute each side. Drain on paper towels.

Step 4

Fry sliced leeks until golden, about 2-3 minutes. Drain on paper towels to cool.

Step 5

Mix lime juice and soy sauce in a small bowl.

Step 6

Marinate tuna in soy sauce-lime juice mixture for 5-10 minutes.

Step 7

Mix mayonnaise with salsa macha and spread about a tablespoon of the mixture on each cooled tostada. Top each tostada with a few slices of tuna, fried leeks, and avocado slices. Serve with lime wedges.