SARAH SAYS: “I created this recipe to use in my Vanilla Orange Frozen Yogurt Push Up Pops Recipe. Oranges do not typically contain enough citric acid to make the recipes work. Find out our secrets to making Orange Curd thicken.”
P.S. An aluminum pan should not be used to prepare lemon curd (or any acidic curd) because it will react with the egg yolks, turning them chartreuse.
FROSTING, ICING, ETC RECIPE HELP

INGREDIENTS

3 large eggs

2 large egg yolks

1/2 cup sugar

pinch salt

1/4 cup fresh orange juice
2 tablespoons fresh lemon juice
2 teaspoons finely grated orange zest
2 teaspoons finely grated lemon zest

6 tablespoons unsalted butter (softened), cut into tablespoons 

NOTE:
Always zest an orange and/or lemon, or remove its peel before squeezing it for its juice!

INSTRUCTIONS
1. Have a strainer, suspended over a bowl, ready near the range.

2. In a heavy noncorrosive saucepan, whisk together the eggs and egg yolks.

3. Whisk in the sugar and salt. Then whisk in the citrus juices and zests.
SARAH SAYS: I like cooking the zest in the curd for more flavor, and then straining it from the curd at the end, for a smoother consistency.

4. Cook over medium-low heat, stirring constantly, for about 6 – 8 minutes, until thickened and resembling hollandaise sauce, which thickly coats a wooden spoon but is still liquid enough to pour.
The mixture will steam.
SARAH SAYS: Do not let it boil or it will curdle. Whenever steaming occurs, remove the pan briefly from the heat, stirring constantly to prevent boiling.

5. When the curd has thickened, pour it at once into the strainer set over a large bowl.
SARAH SAYS: Press it with the back of a spoon until only the coarse residue remains and discard.

6. Let the mixture cool to body temperature – about 98 degrees F.
Whisk in the softened butter, one tablespoon at a time with an Immersion Blender or quickly, with a wire whisk until well blended.
SARAH SAYS: Make sure you really whisk in the butter quickly, otherwise the curd will be greasy.
I am using an Immersion Blender to blend in the butter, but you can use a wire whisk.

STORAGE
SARAH SAYS: Press a piece of plastic wrap on its surface and cut 6 small steam vents in the plastic to cool. Refrigerate the curd, preferably overnight, to thicken. Then, it can be frozen.

Store in the refrigerator in a covered container and consume within 1 week. Orange curd can be frozen for up to 1 month without quality changes when thawed.
To thaw, move the container from the freezer to a refrigerator for 12 – 24 hours before intended use.