Begin by preparing the ingredients: crush the garlic, juice half a lemon, and separate the egg yolks from the egg whites.

Mash the anchovy fillets into a paste using a pestle or fork.

In a large bowl, use an electric or hand mixer to whisk the egg yolks until they are creamy and lightened in color. Incorporate the mustard and continue whisking until you achieve a smooth, paste-like consistency

Gradually add the olive oil, spoon by spoon, to create an emulsion. You can add more oil once the previous portion is well incorporated. Intermittently add lemon juice to maintain the sauce's desired consistency, being cautious not to make it too watery. You may not need to use the entire juiced lemon

Once the mixture reaches a mayo-like consistency, blend in the crushed garlic and anchovy paste. Thoroughly mix everything and season with salt and pepper to taste. Refrigerate until ready to use.