Either make or buy raw tortilla dough. You can substitute flour tortillas as well. Julienne them super thin and fry in 350 degree oil. Drain on paper towels and season with salt and pepper. These will be your garnish
Peel and pull apart the mandarin oranges. Place the segments in a bowl. Cut them in 1/2 if you prefer. make sure to remove the little muscles from the scallops before marinating. They can be tough. Then add in all ingredients except avocado and second lime juice. Refrigerate for at least 30 minutes. Closer to 1 hour is better. This gives time to "cook" the scallops.
Place the flesh of the avocado in a food processor or mixing bowl and puree with lime juice, salt, and pepper.
Serve the ceviche in small bowls or in ceramic spoons as an hors d'ouevre. Garnish with tortilla threads and avocado puree.