- In a medium saucepan of boiling water cook the shrimp and scallops together until they just turn opaque (about 1 to 1½ minutes).
- Drain in a colander and refresh under cold running water.
- Dry over paper towels and half the shrimp crosswise.
- In a large skillet heat ¼ cup of olive oil over high heat.
- Add the mushrooms in an even layer, season with salt and pepper and cook, without turning, until the mushrooms are browned on one side (about 2 minutes).
- Stir and cook the mushrooms until they are tender (about 1 minute longer), add 1 tablespoon of the vinegar and cook until the liquid is evaporated (about 10 seconds).
- Transfer the mushrooms to a plate and allow to cool.
- In a large bowl combine the lobster, the crab,the reserved shrimp and the scallops.
- Stir in the cooled mushrooms, 1 tablespoon of olive oil, the remaining 1 teaspoon of the vinegar and the chopped fresh herbs.
- Toss well to combine tightly pack the seafood salad into four 3½" to 4" ramekins, cover with plastic wrap and refrigerate for 1 hour.
- In a blender, combine the avocado, the garlic, the coriander, the lemon juice and thehot pepper sauce.
- Add the water and blend until smooth.
- With the machine running add the remaining olive oil in a thin stream and blend until completely incorporated.
- To serve, unmold the salads, turning the ramekins over (giving them a tap to release the salad) on to 4 cold plates.
- Spoon a heaping tablespoon of the avocado sauce on either side of the salad and serve immediately.