Sanitize all work areas, cutting boards, equipment and sinks used in preparation of this recipe.
Combine lemon juice, mustard, salt and sugar into a cambro (for use with an immersion blender) or into a vitamix blender.
Blend, while constantly attended, until thoroughly combined and sugar dissolves, about 2 minutes.
While blending, form a swirling vortex and add evoo in a thin steady stream until all oil is incorporated and fully emulsified.
Transfer to a stainless-steel bowl.
Add shallots and capers.
Whisk together until thoroughly combined and ingredients are evenly distributed throughout the vinaigrette. Taste and adjust seasoning as needed.
Transfer to clean food storage containers. Cover, label, date and store refrigerated.
—