What to Do With Leftover Christmas Cookies: Cake, Rum Balls & Cake Pops

Dry, crisp cookies suit crumble toppings, cake bases and rum balls; gingerbread and softened or creamy cookies are best in a no-bake fridge cake; and chocolate ones belong in rum balls and cake pops. What's inside the cookie matters more than what it's called:

• Dry and crisp (unfilled Linzer cookies, vanilla crescents, meringue-style "pracny", nut and coconut cookies): for crumble topping, no-bake cake bases, rum balls and cake pops. These keep the longest.

• With jam (Linzer rounds, stars): for rum balls and cake pops. The jam adds moisture, so you'll need less binder.

• Gingerbread: for a layered no-bake cake. The spices go beautifully with quark or mascarpone.

• With chocolate: for chocolate rum balls and cake pops, where the chocolate disappears into the crumbs.

• With buttercream, egg cream or whipped cream filling (wasp's nests, filled cups, cream horns): only for the next few days, and best used straight away in a fridge cake. They aren't for storing.

• Softened (cream horns or coconut cookies that have absorbed moisture): for a fridge cake, where softness doesn't matter.

Feel free to mix types, just watch out for strong flavors. Gingerbread, coconut and rum will overpower everything else. If what you have left isn't finished cookies but dough trimmings, crumbs from the baking sheet and leftover filling, check out the article Cookie Baking Leftovers: Dough Scraps, Crumbs and Extra Filling.

According to USDA FoodKeeper, dry homemade cookies keep 2–3 weeks at room temperature, about 2 months in the fridge and 8–12 months in the freezer, always in a sealed tin. Cookies with a creamy filling keep only 3–4 days in the fridge. That figure for cream-filled baked goods comes from the Virginia Cooperative Extension storage overview, which is based on FoodKeeper and USDA FSIS guidance.

What this means in practice:

• The clock starts when you bake, not on Christmas Eve. Dry cookies baked in early December are at the end of their room-temperature window by Christmas. Whatever you won't eat right away, put in the fridge or freezer, or use up.

• The freezer is the best option for dry cookies. Thaw them in the closed tin so water doesn't condense on them.

• Cookies with a creamy filling belong in the fridge (at or below 4 °C / 40 °F). According to the USDA (foodsafety.gov), foods with a creamy filling that have spent more than 2 hours above 4 °C should be thrown out. A cool pantry or balcony is no substitute for a fridge, as the temperature there swings during the day.

• Treat finished rum balls, cakes and cake pops containing quark, mascarpone, whipped cream or cream filling as a creamy dessert: in the fridge and within 3–4 days. No agency issues its own time limit for homemade rum balls, so stick to the shortest limit of any ingredient used. Processing doesn't extend the time.

Throw out cookies with any of these signs:

• cookies with mold (white, gray or green fuzz, dark spots). With soft and creamy cookies, throw out the whole box, because mold in soft baked goods spreads deeper than you can see.

• rancid cookies: nuts or butter taste bitter, sharp or like old oil. Rancid cookies would ruin the flavor of the whole cake, so toss them.

• filling that has turned sour, separated, gone watery or smells odd.

Creams made with raw eggs are a topic of their own. The article What to Use Instead of Raw Eggs in No-Bake Christmas Cookies explains how to avoid them.

Rum balls are the quickest way to rescue leftover cookies: crush them finely, combine with fat and rum, and roll into balls. The working ratio is 300 g crumbs + 80–100 g softened butter + 2–3 tablespoons rum + 1–2 tablespoons cocoa.

• Crumbs: blitz the cookies finely in a blender, or crush them with a rolling pin in a bag. Bigger pieces of nuts are fine, but whole pieces of cookie are not, because the ball breaks along them.

• Binder: butter gives you balls that firm up when chilled and hold their shape. You can replace part of the butter with quark, mascarpone or leftover cookie filling. But then the balls belong in the fridge and must be eaten within 3–4 days of when the creamy cookies inside them were baked. Leftover Czech egg liqueur (formally "vaječný likér", eggnog-style) also works in place of some of the rum. You'll find how long an open bottle lasts in the article Egg Liqueur: How Long It Keeps and How to Store It.

• Moisture: cookies with jam, and gingerbread, are moister, so add the binder a spoonful at a time.

• The test: squeeze a handful of the mixture in your palm. If it holds together and doesn't stick to your hand, it's right. If it crumbles, add a spoonful of fat or liquid. If it's smeary, add more crumbs or cocoa.

Roll balls of 15–20 g, coat them in cocoa, coconut or sprinkles, and chill for 30 minutes to firm up. If they fall apart after chilling, the mixture is too dry: put it back in the bowl and add a spoonful of softened butter.

You can make a no-bake cake from leftover cookies in two ways: either press the crumbs into a base and top it with cream, or layer whole cookies with cream and let them soften overnight.

1. Crumb base: for a 20 cm (8 in) pan, mix 250 g crumbs with 80–100 g melted butter. Press firmly into the bottom (the bottom of a glass works well) and chill for 30 minutes until firm. Top with a cream of mascarpone, quark or whipped cream, plus fruit. Dry, crisp cookies are best for the base.

2. Layered cake: in a pan or bowl, layer cookies and cream, and repeat. The cookies soak up moisture from the cream, and in 8–12 hours in the fridge they turn into a soft "base". Gingerbread, softened cream horns and cookies with jam are ideal for this version.

This is also the place for cookies with a creamy filling that need using up. Work them into a cake, keep the whole cake in the fridge and eat it within 3–4 days of when the creamy cookies inside it were baked. Processing doesn't extend the time.

Cake pops from leftover cookies are balls on a stick, dipped in chocolate and decorated with sprinkles. The mixture is the same as for rum balls (without the rum if kids will be eating them), only a bit firmer so it stays on the stick. You may know the same principle from the recipe for chocolate brownie balls.

1. Roll balls of 25–30 g and chill them for 30 minutes. Don't put them in the freezer: a ball that's too cold will crack the coating.

2. Melt the chocolate in a narrow, tall cup. For 20 cake pops, count on at least 200 g, so the ball can be fully submerged, even though only a small part of it ends up as coating.

3. Dip the tip of the stick about 1 cm (½ in) into the chocolate and push it halfway into the ball. Let it set for a moment: the chocolate works as glue.

4. Dip the whole ball, lift it out and gently tap the stick on the rim of the cup to let the excess drip off.

5. Add sprinkles right away, while the chocolate is wet. Sprinkles won't stick to a set coating. Rainbow sprinkles work nicely.

6. Stand the cake pops in a block of styrofoam or a glass of sugar and let them set.

If your balls keep falling off the stick, the article Cake Pops: How to Keep Them on the Stick and the Chocolate From Cracking covers it in detail.

Real chocolate tastes best on cake pops made from leftover cookies, but a fat-based coating is easier to work with. An honest comparison:

• Real chocolate, tempered: glossy, snaps, and holds up at room temperature. Callebaut 811 dark chocolate, for example, melts at 45–50 °C, cools to 27 °C and is worked at 31–32 °C, according to the manufacturer. At home the easiest way is the seeding method: melt two thirds of the chocolate callets to 45 °C, stir in the remaining third and keep stirring until the chocolate reaches 31–32 °C. The callets melt evenly and you don't need to chop them.

• Real chocolate, just melted: tastes the same, but stays softer and can turn gray after a few days (the fat rises to the surface). If you keep the cake pops in the fridge anyway and eat them soon, it doesn't matter at all.

• Supermarket fat-based (confectionery) coating: just melt it and it sets glossy even without tempering. The cocoa butter in it is replaced by vegetable fat, though, so it tastes waxy and sweet. We don't sell it at Yumst, but it's an honest choice when you're mainly in a hurry.

For kids, milk chocolate, which is tempered at lower temperatures, is a better choice than dark. Which Callebaut chocolate to use for what is explained in the article Callebaut 811, 823, W2 and RB2: Which Chocolate for What.

Dry cookies that are no longer crisp: crumble them coarsely and toast on a baking sheet at 150–160 °C (300–320 °F) for 5–8 minutes. The moisture leaves and the crumbs crunch again. Keep an eye on them, as sugar and nuts brown quickly.

Use the crumbs as a topping for:

• baked apples or pears,

• plain yogurt, skyr or quark with fruit,

• ice cream and sundaes,

• crumble: put fruit in a baking dish, top with the crumbs mixed with a little cold butter, and bake until golden.

Put the crumbs in a sealed tin only once they've cooled, otherwise they'll go soft. Vanilla crescents and Linzer cookies work best for this; coconut pieces scorch quickly.

Bake fewer kinds in larger batches, and save the creamy ones for the last week before Christmas. Dry cookies keep for weeks, creamy ones only days, so holiday leftovers are mostly the creamy kind.

The shopping list for Christmas baking spells out how much of everything to buy. When you're choosing what to bake next year, you'll find recipes and tools together on the Christmas cookies page.