Be not afraid - this is very easy. The only problem is it makes about a cup and it only lasts a day or two. So make it when you know it will be consumed (like for potato salad or lots of people having sandwiches). If you want to make less you could look for smaller eggs and decrease the rest of the ingredients; sometimes the Schaners have little guinea fowl eggs. Or if you want to make a big batch, sometimes they have larger turkey eggs.
You are using a raw egg - again, be not afraid. Do you know where your local eggs come from? Do you keep them in the refrigerator once you get them home? Do you use them up and get fresh ones often? Are you immunocompromised? (yes, yes, yes, no) Good, then you have nothing to fear.
1 egg from your backyard or favorite farmer
1 tablespoon fresh lemon juice from a local tree heavy with fruit
1 teaspoon dijon mustard
1 cup oil (more or less, depending on the size of the egg)
½ teaspoon sea salt
pinch cayenne pepper
In a food processor or blender, combine the egg, lemon juice and Dijon mustard. Process on high speed for 15 seconds. With the motor running, pour the oil in a slow, steady stream and process until emulsified. Watch while you're adding the oil: once it's real thick, (it will be harder to incorporate more oil and you don't want to over blend) and the oil just starts to pool on top, STOP. Add the salt and cayenne, and pulse briefly to blend.
Makes a bit more than a cup will keep for about 24 hours.
I never liked mayo until I made it myself. This is sooo much better than the shelf-stable stuff.
Try making with olive oil or half olive oil
Use different types of mustard
Use lime instead of lemon
Stir in chopped fresh herbs
Stir in other spices (black pepper, saffron...)
Make Aoli (garlic mayo): add 2-3 cloves of garlic to the blender first; blend well and then proceed with the rest of the recipe.
Kitchen Tip: How to Crack an Egg
Crack the egg gently (not too soft, not too hard) on a flat surface (e.g. your counter top), not the lip of your bowl. This way, the egg shells don't go into the egg white and you shouldn't get any shell in your recipe. Crack eggs one at a time into a separate small bowl before adding them to your recipe. Then, if you do happen to break little pieces of shell into your egg, they are easily removed.