Hollandaise for One

• 1 large egg yolk, at room temperature
• 4 tablespoons very cold butter, cut in 12 pieces
• About 1 1/2 teaspoons fresh lemon juice
• Salt

1. Warm the yolk slowly in a small, heavy pot, such as Le Creuset, set in a saute pan of barely simmering water, whisking vigorously.
2. When the yolk turns lemon-colored and starts to thicken, add the very cold butter pieces one by one, continuing to whisk steadily.
3. As soon as one piece of butter is incorporated, whisk in the next one.
4. If at any point the sauce starts to bubble or separate, immediately remove the pot from the warmth of the saute pan and set it into a pan of icy water.
5. But you should not have this difficulty if you work slowly and patiently.
6. When all the butter has been absorbed and the sauce is warm and thick, season with at least a teaspoon of lemon juice and salt to your taste.
7. To store any remaining hollandaise, put it in a very small saucerlike bowl and film with plastic wrap.
8. It will keep refrigerated for several days.
9. To warm up, let it come to room temperature slowly, then put the sauce in a small pot over warm water, and whisk furiously.
10. It should recover its creamy consistency.
11. If it starts to curdle, quickly remove the pan from the heat and whisk a teaspoon of cold cream into the sauce.
12. Taste and add a little more lemon juice if needed.

egg yolk, very cold butter, lemon juice, salt

Taken from www.epicurious.com/recipes/food/views/hollandaise-for-one-378397 (may not work)