Put 2-3 inches of water into a sauce pan and simmer. Do not let it boil. Simmer on the lowest heat.
Put your egg yolks into a glass bowl (I find metal bowls heat faster than glass bowls and may curdle your eggs) with the lemon juice. Vigorously mix with a whisk.
Put the glass bowl over the sauce pan. The simmering water's evaporation will touch the glass bowl and this will cook our hollandaise sauce.
The trick to a hollandaise sauce is to never stop whisking. You will build some serious arm muscles here.
While whisking, slowly drizzle your melted ghee into the yolks. Drizzle like 1 tbsp at a time really slowly. Repeat this step until all of the ghee has been added. Continue whisking until your sauce starts to thicken.
Take it off the heat and continue whisking. Once the desired thickness is achieved, sprinkle the salt and whisk in. Set aside.
If you notice your sauce may break, take the bowl out of the saucepan and continue whisking. If your sauce has already broken, you could try to add 1-2 tbsp of cold water and whisk it in extremely quickly. It may or may not work depending on how broken your sauce is.
If your sauce is not thick enough, continue whisking. It will start to thicken as the eggs cook with the heat.