Heat a skillet over medium heat. Pat the lobster tails completely dry with paper towels. Add the butter to the skillet. Once melted, add the lobster tails and cook until they are just opaque, flipping once, for about 4 to 5 minutes. Remove the lobster - and chop one of them up into pieces.
Place the avocados, cilantro, onion, lime juice, salt and pepper to a bowl and mash it! Mash and stir until everything is combined. Make it as smooth or as chunky as you’d like! Taste and season with additional salt, pepper or lime juice if needed.
Top the guacamole with the chopped lobster. Add on a few cherry tomatoes, some pepper slices and fresh cilantro if desired. Top with another full lobster tail for a pretty presentation!