This Biscoff twist on tiramisu has thick layers of rum & espresso-soaked Biscoff cookies alternating with the most luxurious mascarpone custard delicately flavored with cookie butter, rum, and spices. It’s the most mindblowingly delicious holiday dessert that no one can stop eating. 
This Biscoff tiramisu is magical
I cannot put into words just how heavenly this Biscoff tiramisu is. It’s like eating a delicate, luxuriously creamy cloud that’s exploding with rich, warm, cozy, festive flavors like deep caramel & brown sugar, cinnamon, espresso, rum, and cocoa. Of all Christmas desserts, this is the one everyone keeps coming back for. It has such a light and luscious mouthfeel that you really can’t resist another bite. And it’s the one I would be eating everyday indefinitely if I could make it last that long.
Not your classic tiramisu
If you’re thinking that this does not sound like “authentic” tiramisu, you are correct. Tiramisu is traditionally composed of ladyfingers (a light sponge cookie) soaked in coffee; a simple custard made from egg yolks, sugar, and mascarpone; and cocoa. Unlike most modern recipes, the “traditional” version doesn’t include whipped cream, alcohol, or vanilla, and the yolks are not tempered.
Nevertheless, I thought tiramisu was the most fitting way to communicate the essence, taste, and textures that you’re getting in this recipe. Like the custard of tiramisu, this custard is made with egg yolks, sugar, and mascarpone. But, we’ve added whipped cream for a delicate & voluminous consistency, plus Biscoff cookie butter, rum, cinnamon, vanilla, and sea salt for smooth, warm, cozy flavor throughout every bite. In place of ladyfingers, we’re using a double layer of Biscoff cookies soaked in espresso and rum for thick bites of super soft cookie contrasting with the cream. Finally, in addition to cocoa, a sprinkle of cinnamon on top compliments the flavors beautifully.
I realize whisking up an egg yolk-based custard from scratch may seem intimidating, but this is NOT difficult to make. It just takes a little patience and attention to your ingredients, but I promise it is simpler than you think.
- Whisk egg yolks and sugar together (over steam) until fluffy, then add in your cookie butter, rum, and spices.
- GENTLY stir in softened mascarpone.
- Whip some cream and GENTLY fold that in. Custard is done!
- Dip cookies in espresso and rum.
- Layer it all up and dust with cinnamon and cocoa.
It’s that simple! Cover and refrigerate for several hours or overnight to let the custard set and the flavors marry. Then when you pull the cover back to serve, you’re greeted by the deepest, warmest, most mouthwatering aroma of coffee, rum, cinnamon, and cocoa. And it tastes better than any restaurant custard dessert out there.
What can go wrong
More importantly, how you can make sure these things don’t go wrong:
- Scrambled eggs: (1) If you overheat the egg yolks, you’ll make scrambled eggs instead of custard –> Don’t let your mixing bowl touch the boiling water or sides of the pot directly. (2) If you stop stirring while the bowl is hot, you’ll make more scrambled eggs –> Stir CONSTANTLY while bowl is over the steam, and KEEP STIRRING when you remove the mixing bowl from the heat, until it’s cooled to room temperature.
- Lumpy custard: Less is more when it comes to assembling your custard. (1) If you whip the mascarpone in too vigorously, it may separate, leaving you with a lumpy cream. –> Use a spoon to gently stir the mascarpone in by hand, just until it’s incorporated. (2) If you over-whip your heavy cream, that can also create lumps. –> Aim for a soft whipped cream and stop beating when it holds its shape. If you reach curds of whipped cream, you’ve gone too far.
- Eaten too quickly: This one I have a harder time with… Some strategies include hiding portions of the tiramisu in disguised containers (“Black Bean Soup,” “Cool Whip,” etc.), or serving it with a really pretty cake or pie for distraction. Let me know in the comments what else you can come up with.
Quick note on raw eggs
If you’re worried about eating raw eggs, rest assured: The egg yolks in this recipe are tempered over hot steam while you whisk them with the sugar. And even if you cheat a little bit (or skip that step completely like in many recipes), it is very rare that high-quality store-bought eggs carry salmonella. Officially, it’s never completely and totally “safe” to consume raw eggs because the heat is necessary to kill bacteria.
Biscoff Tiramisu
This Biscoff twist on tiramisu has thick layers of rum & espresso-soaked Biscoff cookies alternating with the most luxurious mascarpone custard delicately flavored with cookie butter, rum, and spices. It's the most mindblowingly delicious holiday dessert that no one can stop eating.
Notes
This recipe is written to fit a 9” to 10” square (or 2.5 - 3 quart) baking dish. If using anything larger, you can double the custard and adjust the number of cookies to fill the pan.
Ingredients
For the custard:
- 3 egg yolks
- 1/4 cup + 2 Tbsp granulated sugar
- 2 Tbsp smooth Biscoff cookie butter
- 2 Tbsp rum (dark or light)
- 1/2 tsp vanilla extract
- 1/4 tsp ground cinnamon
- pinch sea salt
- 7 oz mascarpone cheese, softened
- 1 cup cold heavy cream
For the soak:
- 1/2 cup strong espresso (or 1/2 cup hot water + 2 tsp instant espresso)
- 2 tsp granulated sugar
- 2 Tbsp rum (dark or light)
- about 30-40 large Biscoff cookies, adjusted to the size and shape of your pan
- unsweetened cocoa and cinnamon for dusting the top
Instructions
- With an electric hand mixer or by hand, whisk 3 egg yolks with 1/4 cup + 2 Tbsp granulated sugar. While whisking continuously, place the mixing bowl over a small pot of simmering water and continue mixing on medium speed for about 10 minutes. Make sure the mixing bowl is not in direct contact with the hot water or the metal pot. (If overheated, the egg yolks will start to cook.) The goal is to use the heat to help dissolve the sugar while creating a creamy, fluffy consistency. The mixture should be light in color and roughly doubled in size. If after 10 minutes, you still feel some grittiness from the sugar, don’t fret; the alcohol will help us out.
- While whisking continuously, remove the bowl from the heat, and KEEP WHISKING for another couple minutes, until the bowl has fully cooled.
- Mix in 2 Tbsp smooth cookie butter until fully combined (it will look stiff—that’s ok, keep going!), then 2 Tbsp rum, 1/2 tsp vanilla, 1/4 tsp cinnamon, and a pinch sea salt. Mix on medium speed 2-3 minutes, until completely smooth.
- Using a wooden spoon or rubber spatula, GENTLY stir in 7 oz softened mascarpone, JUST until fully incorporated and smooth. Do not over-mix. (Over-mixing the mascarpone risks separation and a lumpy cream.)
- In a separate bowl, add 1 cup cold heavy cream. Using an electric mixer, mix on low speed until the cream starts to thicken, then gradually increase speed to whip the cream to soft peaks, about 5 minutes total. (Make sure it is soft and not whipped to curds, as over-beating the cream can also lead to separation.)
- Using a wooden spoon or rubber spatula, fold half of the whipped cream into the mascarpone mixture. Then fold in the remaining whipped cream, just until evenly combined. Don’t over-mix.
- Microwave 1/2 cup water until boiling, then stir in 2 tsp instant espresso (or brew 1/2 cup espresso). Mix 2 tsp sugar and 2 Tbsp rum with the espresso. Transfer to a bowl or flat-bottomed container for dipping your cookies.
- Quickly dip Biscoff cookies one at a time in the coffee mixture, let excess drip off, then place them in a DOUBLE layer on the bottom of a deep, 9" to 10" square baking dish.
- Pour half of the cream over the cookies and spread evenly.
- Repeat with another double layer of cookies and remaining cream.
- Dust the top with cocoa and cinnamon.
- Cover tightly and refrigerate at least 4-6 hours, or overnight, before serving. Store refrigerated.