01 - Combine tuna cubes with soy sauce, sesame oil, lime juice, and chili flakes in a bowl. Let marinate while preparing other components.
02 - Whisk together sour cream, lime juice, and chopped pickled jalapeños until smooth. Season with salt and pepper to taste. Set aside.
03 - Preheat a skillet over medium-high heat. Sear marinated tuna for 30-60 seconds per side, leaving center rare. Alternatively, leave raw for poke-style preparation.
04 - Arrange tortilla chips on a serving platter or ovenproof tray. Sprinkle cheese evenly over chips and broil for 1-2 minutes until melted, if desired.
05 - Top chips with seared tuna, avocado, tomatoes, red onion, jalapeño slices, and fresh cilantro. Drizzle generously with jalapeño-lime crema.
06 - Serve while chips remain crisp and toppings are fresh for optimal texture and flavor.