Prepare the Avocado Mousse: Halve the avocados and remove the pits. In a food processor, add the avocado flesh, lime juice, sour cream or Greek yogurt, and fresh herbs. Blend until smooth and creamy, seasoning with salt and pepper.

Assemble the Mousse: Spoon the mousse into serving glasses, filling them three-quarters full. Use a spatula to smooth the tops.

Add the Smoked Salmon: Lay slices of smoked salmon generously atop the avocado mousse, creating an elegant presentation.

Chill and Enhance Flavors: Cover with plastic wrap and refrigerate for at least 30 minutes to allow flavors to meld.

Garnish and Serve: Before serving, garnish with additional herbs and serve alongside crusty bread or crackers.