Thin Mint & Irish Cream Biscuit Cake
Give this boozy biscuit cake a try this St. Patty's Day! Full of Irish cream white chocolate ganache, minty chocolate cookies, and a dark chocolate glaze, your taste buds will be the lucky ones.
Originally I wanted to use actual Girl Scout cookies for this recipe, but they weren’t selling them yet! Soooo I just made my own from scratch. Now you get to reap the benefits. Lucky you!
Servings: 10 to 12 | Prep Time: 1 h 45 m | Cook Time: 40 to 50 m | Chill Time: 3 h 30 m
Hand-mixer / Stand-mixer
Plastic wrap
Parchment paper
Wire racks
9” springform pan
Double boiler / Heat-safe bowl and saucepan
Offset spatula
Bench scraper
Food processor
Mint Cookies:
2 ⅔ cups flour
⅓ cup cornstarch
6 tbsp cocoa powder
2 tbsp black cocoa powder
2 tsp baking powder
1 ½ tsp salt
1 cup butter, room temp
1 ½ cups sugar
2 egg whites, room temp
½ cup vegetable oil
2 tsp vanilla
1 tsp peppermint extract
White Chocolate & Irish Cream Filling:
18 oz white chocolate
1 cup + 2 tbsp butter
3 tbsp golden syrup
½ cup Irish cream
20 oz (about 40) mint cookies
Irish Cream Ganache Glaze:
200 g dark chocolate, chopped
50 g white chocolate, chopped
125 g Irish cream, divided
Assembly:
Fresh mint
Mint Cookies (35 minutes + 40 to 50 minutes baking + 1 hour chilling)
In a small bowl, sift together the flour, corn starch, cocoa powder, black cocoa powder, baking powder, and salt. Set aside.
In a large bowl, with a hand-mixer or stand-mixer, beat the butter and sugar together until fluffy, about 2 minutes.
Beat in the egg whites, oil, vanilla, and peppermint extract until well-combined.
Add the flour mixture, in two batches, to the butter mixture, beating well after each addition.
Divide the dough in half and roll each portion into a cylinder about 2” in diameter.
Wrap each cylinder in plastic wrap and transfer to the freezer to chill, at least 1 hour.
Preheat the oven to 350° F and line two baking sheets with parchment paper.
Remove the dough from the freezer, one portion at a time.
Using a sharp knife, slice the dough into cookies about ¼” thick.
Transfer a dozen cookies to the baking sheet and bake for 8 to 10 minutes. Keep any raw dough in the freezer until ready to bake.
Let cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.
Repeat with the remaining dough, about 60 cookies in total. Set aside.
White Chocolate & Irish Cream Filling (25 minutes + 2 hours chilling)
Grease and line a 9” springform cake pan with parchment paper. Set aside.
In the top of a double boiler, melt the white chocolate, butter, and golden syrup together. Don’t worry if the mixture looks split at this point.
Gradually whisk in the Irish cream until mixture comes together and is completely smooth. Remove from the heat and let cool for 15 minutes.
Weigh out 20 oz of the cooled mint cookies (about 40). Set aside the remaining cookies until assembly.
On a cutting board, chop the cookies in half and add to the cooled white chocolate mixture.
Gently mix with a wooden spoon until the cookie pieces are evenly coated. Be careful not to overmix.
Press the mixture into the prepared pan, making sure to fill any gaps, and smooth out the top with an offset spatula.
Cover with plastic wrap and transfer to the fridge to chill for at least 2 hours or overnight.
Irish Cream Ganache Glaze (20 minutes)
Place the chopped dark chocolate in a medium glass bowl and the chopped white chocolate in a small glass bowl. Set aside.
Microwave 100 g Irish cream until just starting to bubble at the edges, about 15 to 25 seconds.
Pour over the dark chocolate and set aside for 5 minutes. Meanwhile, prepare the white chocolate glaze.
Microwave the remaining 25 g Irish cream until just bubbling at the edges, about 10 to 15 seconds.
Pour over the white chocolate and set aside for 5 minutes.
Stir the dark chocolate and cream together until completely smooth and set aside. If needed, add more cream and microwave to get a consistency that is just pourable.
Do the same for the white chocolate, stirring until completely smooth and setting aside.
Assembly (25 minutes + 30 minutes chilling)
Take the cake out of the fridge and run a knife around the edge to loosen from the sides of the pan.
Unlock the springform pan and carefully remove the sides.
Flip the cake over onto a wire rack. Remove the bottom of the pan and the parchment paper.
If needed, scrape the top and sides with a bench scraper until the cake is nice and smooth.
Place the cake and the wire rack on a baking sheet.
Pour the dark chocolate ganache over the cake, completely covering the top and sides. Smooth with an offset spatula, working quickly before the ganache sets.
Immediately drizzle the white chocolate ganache in a swirling pattern onto the top of the cake. Set cake aside.
In a food processor, pulse the remaining chocolate cookies into small crumbs.
Using your hands, press the cookie crumbs gently into the sides of the cake until the sides are completely covered.
Refrigerate the cake for at least 30 minutes so the ganache sets.
Just before serving, decorate the top with a few sprigs of fresh mint.
Serve immediately. Leftovers may be stored in the fridge for up to a week.
Enjoy!
Be sure to check out my Best Practices page for tips on how to make this recipe yourself. Let me know in the comments if you have any questions and feel free to tag me on Instagram @made.by.shade if you make it!
-Shade