Begin by scooping the flesh of two ripe avocados into a food processor. Add the juice of one fresh lime and a handful of your chosen fresh herbs, such as cilantro or dill. Blend the mixture on high for about 30 seconds, or until the ingredients are smooth and combined.

Next, add half a cup of sour cream or Greek yogurt to the avocado mixture, enhancing the mousse's creamy texture. Process again for another 30–40 seconds, ensuring everything is fully incorporated.

Taste the mousse and adjust the seasoning according to your preference, adding a pinch of salt or an extra squeeze of lime juice if desired.

Transfer the creamy mousse into serving dishes, smoothing the top for a polished look. Cover each dish with plastic wrap and refrigerate for at least 1 hour.

When ready to serve, top each dish with slices of Christmas smoked salmon, garnishing with additional fresh herbs.