In a medium bowl, combine onion, lime juice, cilantro, tomato, olive oil, 1/8 tsp salt and fresh pepper, to taste.: The first sensory cue is the aroma of citrus and fresh herbs releasing as you toss these ingredients. You will notice the sharpness of the red onion mellow a bit as it meets the lime juice , and the colors of the tomato and cilantro become brighter. This mix serves as the flavor foundation for the salad, so taste and adjust the seasoning now. A common mistake is overwatering the mixture, which makes the filling soggy; if that happens, drain excess liquid or pat the tomato pieces dry before adding.
Add crab meat and gently toss.: Expect a subtle seaside aroma as you fold in the crab meat . Use a light hand to preserve the lumps, moving with a folding motion rather than vigorous stirring, which helps maintain the delicate flakes. The visual cue is intact white pieces of crab scattered through the dressing. If you mash the meat too hard, the salad will lose its luxurious texture, so stop as soon as the ingredients are evenly coated.
Cut the avocado open, remove pit and peel the skin or spoon the avocado out.: When you cut into the avocado , you should hear a whisper of resistance and see a smooth, pale green flesh. The smell is faintly nutty and green. Remove the pit carefully by tapping and twisting, then either peel the skin away or scoop the flesh with a spoon for a softer presentation. A frequent error is using an overripe fruit that collapses; choose one that yields to gentle pressure but still holds shape.
Season with remaining 1/8 tsp salt and fill the avocado halves equally with crab salad.: After seasoning, the first thing you will notice is how the salt sharpens the sweet notes of the crab meat and pulls the flavors together. Spoon the crab salad into the avocado hollows, aiming for even portions so each half feels balanced. The visual should be colorful, with white crab, green avocado, red tomato, and flecks of cilantro . Avoid overfilling, which can make each bite messy to eat.
This makes 2 servings, place on two plates with lettuce if you wish and serve.: The final presentation should look effortless and composed, especially if you nest each half on a leaf of butter lettuce . Listen for the muted sound of placing the pieces onto the plate, and take a moment to appreciate the contrast in textures. Serve immediately to preserve the fresh crunch and creamy mouthfeel. A common pitfall is letting the assembled dish sit too long, which can cause the avocado to discolor and the salad to release moisture.