Combine the base ingredients:

Add the anchovies, smoked chicken garum, white balsamic (or white wine vinegar), water, and a few twists of black pepper to a tall measuring jug or mixing cup.

Blend:

Blend until smooth using a stick blender.

Add the mayonnaise:

Add the mayonnaise and blend again until you get a creamy, uniform dressing.

Adjust the consistency:

If the dressing is too thick, add a little extra water—bit by bit—until you reach the desired consistency.