Americanvegetarian

Leftover Egg Yolk Shortbread Cookies

Name: Leftover Egg Yolk Shortbread Cookies
Prep time: 50 min
Cook time: 15 min
Total time: 65 min
Yield: 4 servings
Cuisine: USA
Ingredients: 1 cup unsalted butter; 1/2 cup powdered sugar; 4 large egg yolks; 2 tsp lemon zest; 1 tsp vanilla extract; 1/2 tsp fine salt; 2 cups all-purpose flour; 2 tbsp coarse or sparkling sugar

Buttery slice-and-bake shortbread cookies made with leftover egg yolks and a little lemon zest. Turns the yolks left from meringues or macarons into two dozen tender cookies in about an hour.

65 minsEasy4 servings125 kcal

Making meringue or a white cake leaves you with a bowl of yolks and nothing to do with them. These shortbread cookies are the answer: four yolks, a stick of butter, and a lemon's worth of zest turn into two dozen crisp, buttery cookies with barely any effort.

Yolks do real work here. They add fat and help the dough hold together without the protein that makes egg-white cookies chewy, so the texture stays rich and crumbly. Powdered sugar instead of granulated keeps the crumb fine, and the lemon zest keeps a buttery cookie from tasting flat.

Expect pale, firm cookies with lightly golden edges, a fine sandy crumb, and a bright hint of lemon. They are sturdy enough to dunk in tea or coffee and keep well, which makes them worth the batch.

shopping_basketIngredients

1 cup unsalted buttersoftened to room temperature
1/2 cup powdered sugaralso called confectioners' sugar
4 large egg yolksleftover, at room temperature
2 tsp lemon zestfinely grated, about 1 lemon
1 tsp vanilla extract
1/2 tsp fine salt
2 cups all-purpose flour
2 tbsp coarse or sparkling sugarfor rolling the log, optional

Nutrition Per Serving

Calories

125

Protein

Fat

Carbs

10g

restaurantInstructions

Cream the butter and sugar

Beat the butter and powdered sugar in a large bowl with an electric mixer on medium speed for 2 to 3 minutes. It should turn noticeably paler and look fluffy and smooth, with no grainy sugar visible. This trapped air is part of what keeps the cookies light.

Add the yolks and flavorings

Add the egg yolks, lemon zest, vanilla, and salt. Beat on medium speed for 1 to 2 minutes until completely smooth and uniform in color, with no streaks of yolk. Scrape down the sides of the bowl once halfway through.

Mix in the flour

Add the flour in two batches, mixing on low speed just until the dough comes together. Stop while it still looks slightly shaggy; a few floury patches are fine. Overmixing develops gluten and turns shortbread tough instead of tender.

Shape into a log and chill

Gather the dough into a log about 2 inches in diameter on a sheet of plastic wrap. Wrap it tightly and refrigerate for at least 30 minutes, until firm to the touch. Firm dough slices into clean rounds; soft dough squashes and loses its shape.

Slice and arrange the cookies

Heat the oven to 325°F (165°C) and line a baking sheet with parchment. Cut the chilled log into rounds about 1/4 inch thick. If using the coarse sugar, roll the sides of each round in it so the edges are coated. Arrange 1 inch apart on the sheet.

Bake until the edges turn golden

Bake 12 to 14 minutes, until the edges are lightly golden but the centers still look pale. The heat of a 325°F oven for this long takes the cookies well past the 160°F (71°C) needed for egg dishes, so the yolks are fully cooked. Let them cool on the pan for 5 minutes, then move to a wire rack.

timer

Cooking Mode

Keep your screen awake with step-by-step guidance.

lightbulbTips for success

Use softened butter, not melted. Softened butter traps air when creamed, which keeps the cookies light; melted butter makes a greasy dough that spreads into thin, tough discs.
Chill the log the full 30 minutes. Cold dough slices into clean rounds and holds its shape in the oven, so the cookies bake up even instead of spreading.
Stop mixing the moment the flour disappears. Shortbread should be crumbly, and every extra turn of the mixer develops gluten, which is the opposite of what you want.
Slice thick, not thin. Quarter-inch rounds bake through without the edges burning; thinner slices brown before the centers set.

swap_horizSubstitutions

No lemon zest? Use 1 teaspoon of orange zest, or 1/2 teaspoon lemon extract.
Salted butter works; use it in place of unsalted and skip the 1/2 teaspoon of salt.
No powdered sugar? Use 1/3 cup granulated sugar; the cookies will be a little crisper and less fine-crumbed.
Gluten-free: replace the flour with a 1:1 gluten-free baking blend; chill the log a full hour so it slices cleanly.

restaurantWhat to serve with it

Serve with tea or coffee, or sandwich two together with a spoonful of jam or lemon curd. They also make a good base for ice cream sandwiches with vanilla ice cream.

kitchenStorage & reheating

Keeps up to 1 week in an airtight container at room temperature. Cool within 2 hours of baking. The unbaked dough log freezes for up to 2 months wrapped tightly in plastic; baked cookies freeze for up to 2 months in a zip-top bag.

To reheat: These are best at room temperature. If they soften after a few days, warm them on a sheet pan in a 300°F (150°C) oven for 5 minutes to crisp them back up.

Recipe FAQ

Why use just egg yolks instead of whole eggs?expand_more

Yolks add fat and emulsify the dough without the protein and water that egg whites bring. Whole eggs make shortbread more cake-like and less crisp; these extra yolks keep the texture rich and tender with a fine, short crumb.

Can I freeze the dough log?expand_more

Yes, and it is a good move. Roll the dough into the log, wrap it tightly, and freeze it for up to 2 months. Slice straight from frozen, adding 1 to 2 minutes to the bake time.

Why did my cookies spread and go flat?expand_more

Two usual causes: butter that was melted instead of softened, which makes the dough too soft to hold its shape, or skipping the chill step. Soften the butter until it holds a dent from your finger, and chill the log until it is firm before slicing.

Why are my cookies tough instead of tender?expand_more

You probably overmixed after adding the flour. Once flour hits liquid, mixing develops gluten, and gluten is what makes bread chewy and shortbread tough. Stir on low only until the dough just comes together; a few streaks of flour are better than a smooth dough.