Heat a heavy skillet over medium-high heat with 1/4 cup vegetable oil (or preheat oven to 425°F/220°C if baking). If frying: when oil shimmers, fry tortillas one or two at a time for 45–60 seconds per side until crisp and golden. Transfer to a paper towel-lined tray and season immediately with 1 tsp fine sea salt. If baking: brush each tortilla lightly with oil on both sides, place on a baking sheet, and bake 6–8 minutes per side until crisp, flipping once; season with salt.

Chipotle Aioli

In a small bowl, whisk together 1/2 cup mayonnaise, 1 tsp minced chipotle, 1/2 tsp adobo sauce, 1 tsp lime juice, 1/2 tsp minced garlic, 1/2 tsp honey (optional) and 1/8 tsp salt until smooth and well combined. Taste and adjust heat or acidity — add more adobo or chipotle for heat, or more lime/honey to balance. Chill in refrigerator while assembling (at least 10 minutes) to let flavors meld.

Salsa Fresca

Combine 2 cups finely diced tomatoes, 1/4 cup red onion, 2 tablespoons chopped cilantro, 1 tablespoon lime juice, 1/2 teaspoon salt and 1/8 teaspoon black pepper in a bowl. Stir gently, then let sit 5–10 minutes at room temperature to marry flavors. Taste and adjust seasoning.

Crabmeat Salad

In a medium bowl, gently toss 12 oz lump crabmeat with 2 tablespoons lime juice, 1 tablespoon olive oil, 1 tablespoon finely chopped shallot, 2 tablespoons chopped cilantro, 1 teaspoon finely diced jalapeño, 1/2 teaspoon salt and 1/4 teaspoon black pepper. Handle crab carefully to keep lumps intact. Refrigerate briefly (5–10 minutes) if needed — do not over-chill.

Assembly & Garnish

Lay out 6 crisp blue corn tostadas. Spread about 1 tablespoon chipotle aioli on each tostada (reserve any extra for serving). Divide shredded romaine evenly among tostadas (about 2–3 tablespoons per tostada). Spoon the crabmeat salad evenly over the lettuce (about 2 oz crab per tostada). Top each with 2–3 tablespoons salsa fresca, 3–4 thin avocado slices, and a sprinkle of chopped cilantro or micro cilantro. Finish with a light squeeze of lime wedge over each tostada.

Serve immediately so tostadas remain crisp. Provide extra chipotle aioli and lime wedges at the table.