Place the room temp egg in a food processor OR a tall small bowl utilizing an immersion blender. Whip for 30 seconds. *If you have a smaller bowl attachment for your food processor, use it for best results.
Add all the other ingredients except the oil.
Measure the oil in a measuring cup with a pouring spout.
SLOWLY pour in about 1/2 the oil in a VERY THIN stream while the food processor is set on high or puree. You will notice the mayo starting to thicken a bit. Continue pouring the oil VERY SLOWLY in THIN stream until you reach the thickness you desire.
Taste and add more spices if you desire.
Transfer the mayo to a small jar or glass container for storage.
NOTES: Unless you like a very strong flavor, avoid olive oil. Avocado is much more neutral. The lemon is what makes this recipe special especially if you like Duke's Mayo. The homemade mayo will last about 2 weeks in your fridge.