Although my palette is mainly chromatic, I just need to have Yellow Ochre on my palette. Ochre is a series 1 paint, it's a cheap and versatile colour. I also like the idea that it has been one of the first pigments ever used by man.
It is thick and opaque and it combines very well with the transparent colours on the palette, allowing me to make thick mixtures. I use W&N or MH Yellow Ochre. Recently I also have been trying MH Raw Sienna, I am learning about its use, for the moment I like the consistency very much.
Another yellow I use regularly is MH Lemon Yellow. Harding claims on his website that he is probably the only colourman to make it.
I suggest to my students that when they want to lighten a mixture for shadows in flesh, they should first reach for yellow ochre and then for lemon yellow. Again this is a strategy to avoid mixing white in the darks with the danger of making the whole painting go chalky.
I also use lemon yellow in combination with reds and blues, as if it was a warmer version of white.
My last essential yellow is W&N Green Gold. I don't know why it is called green, if you mix it with a little bit of white you would see that it produces an acid yellow. It is a transparent colour that has a real zing.
Since it is transparent, it will not modify the tone of a mixture, but it would give it a twist towards yellow. Mix it with blue to make a range of greens, with ochre to turn into a greenish hue, with oranges, reds and magentas for even warmer, tangy mixtures.
Of course, if I am painting a lemon I might have to reach for a cadmium yellow, but otherwise these three yellows are all I need.