|White vinegar||4 Tablespoon|
|Butter||8 Ounce (250 Gram)|
|Lemon juice||1 Tablespoon|
Put vinegar, chopped shallots and peppercorns into pan, bring to boil, reduce heat, simmer very gently uncovered until mixture is reduced by half.
Strain, reserve liquid.
Put egg yolks in top of double saucepan, add cooled vinegar, mix well.
Put top of double saucepan over simmering water, gradually add butter, stir constantly until mixture is thick and creamy; remove from heat immediately.
Add lemon juice, season with salt and pepper.
Put sauce in blender, add peeled and chopped avocado, blend on medium speed until smooth.
Spoon sauce into serving bowl.