Basic Lemon or Lime Curd

Why I Love This Recipe
Ingredients You'll Need
1/2 cup fresh lemon juice (*may also use lime)
1 cup sugar
1/4 tsp. salt
9 egg yolks
1/2 cup unsalted butter
1 Tb. + 1 tsp. freshly grated lemon zest (or lime if using lime juice)
Directions
Whisk yolks & sugar in heavy saucepan until blended.
Whisk in salt, lemon juice, and butter.
Cook over medium-low heat, stirring continually, until thick (should 'coat' the back of a wooden spoon) but still pourable.
*DO NOT BOIL* !!!
Pour into fine sieve or chinois & push through with wooden spoon.
Stir in zest.
Cool quickly by submerging into ice water bath; cover tightly with saran wrap & refrigerate immediately.