Mayonnaise - cooking recipe

Ingredients

2 eggs, beaten
1/4 c. sugar
1 tsp. ground mustard
1 Tbsp. flour
1/2 c. water
1/2 c. vinegar
1/2 tsp. salt
1 Tbsp. butter

Preparation

Cream one-half cup of butter, add the yolks of four eggs, one at a time, stirring well after each addition.
Add two tablespoons of lemon juice, a small quantity at a time, one teaspoon of salt, one-fourth teaspoon of white pepper and very little cayenne pepper; then add one-half cup boiling water and cook in a double boiler until thick as soft custard.