there are few things, as simple and as satisfying to make, as mayonnaise. without much effort you can transform a handful ingredients into something completely different. and something that if you've never made it at home before, you are most likely used to buying bottled, and regarding as if it was simply another form of butter. (that said making butter still gives me a little kick of enthusiasm, even if normally it is the result of mistakenly leaving the cream whipping for too long in the mixer. the leftover buttermilk is sloshing all over the place and making a mess. and i'm probably a little annoyed. then i turn everything off, clean up, and, there it is, accidental butter! so much cooler than if you leave something in the oven for too long. but i digress.)
on the other hand making mayonnaise come together is not as simple as it seems! and can be very frustrating. mayonnaise is in the end a stable but delicate emulsion, which becomes un-fluid when the oil particles are dispersed well and want to simultaneously move together. this creates a kind of simultaneous tension causing the mayonnaise to harden and become semi solid. it is frustrating when this refuses to happen or if it breaks (some oil particles succeed in uniting and the others are joining them easily...). important are a few things. that the egg yolk is at room temperature. incorporating the oil slowly. and the use of mustard as a stabilizer.
the classic method calls for a bowl and a whisk. and while there is nothing wrong with that method, i prefer to use an emersion blender (as for almost all tricky emulsions) and the measuring beaker that comes with the blender or something similar, important is that it is slim and tall, so as to be able to regulate the amount of oil mixing with the egg yolk.
fill beaker with around 250ml (bit more than a cup) of a mild oil such as sunflower seed oil. and drop one egg yolk (you can add more for a more robust flavour and color as I did for the carciofi fritti). carefully place blender over the yolk without dispersing the yolk. in the sense that the head of the blender is covering the yolk. begin to blend. if everything works well, the mixture will immediately seize under the blender head and begin to venture out from underneath. continue blending and slowly lift to incorporate a little oil at a time into the seized semi solid mixture. When everything is incorporated you can add the lemon juice, salt and mustard mixture below. I used alot (2 whole lemons) because i wanted it to be lemony. half to one lemon(depending) is enough normally.
if though on the other hand the mixture never seizes or breaks halfway, there are two options. the classic drop one egg yolk again and start over. as you will see advised all over the net for the classic bowl method. or drop a little of the lemon mustard mixture, which will sink to the bottom, as it is heavier than the oil, and proceed as before. more often than not the mixture will immediately seize!
as in this case, where twice an extra yolk was added, but it kept breaking (they were cold from the fridge). i dropped some lemon juice and stabilizing mustard mixture and voila:
lemon and black pepper mayonnaise