Step 1

Place ¼ cup of oil in a food processor, and add the egg, ground mustard, and salt.

Step 2

Process thoroughly, for about 30 seconds, until combined and pale yellow in color.

Step 3

With the blender running, slowly drizzle in the remaining oil until the mixture is emulsified and thick. Adding the oil slowly makes for a creamier mayonnaise, and if you pour too fast, the emulsion may break. The total pouring time to aim for should be about 90 seconds.

Step 4

With the food processor still running, add the lemon juice, and mix briefly, for only about 5-10 seconds, until incorporated.

Step 5

The mayonnaise is now ready to be used. Enjoy!