Description
Delight in these Butterscotch Marshmallow Sandwich Cookies, featuring soft, chewy cookies enriched with Biscoff cookie butter and a luscious butterscotch marshmallow frosting. Perfectly baked to tender edges and filled with a creamy, sweet frosting that creates the ultimate cookie sandwich treat ideal for sharing or savoring as a special dessert.
Ingredients
Cookie Dough
- 1 cup + 2 Tablespoons (135g) all-purpose flour
- 10 Biscoff cookies (crushed into a fine crumb, about ½ cup)
- 1 teaspoon cornstarch
- ½ teaspoon baking soda
- ¼ teaspoon baking powder
- ½ teaspoon salt
- ½ cup (113g) unsalted butter (softened to room temperature)
- ¾ cup (150g) firmly packed light brown sugar
- 1 large egg (at room temperature)
- 1 teaspoon vanilla extract
- ½ cup (120g) Biscoff cookie butter
Butterscotch Marshmallow Frosting
- 4 ounces (113g) butterscotch chips
- ½ cup (113g) unsalted butter (softened to room temperature)
- 2 ounces (57g) marshmallow fluff
- 1 to 2 Tablespoons (15-30mL) room temperature water
- 1 and ¾ cups (210g) powdered sugar
- ¼ teaspoon salt
Instructions
- Preheat and Prepare Baking Sheet: Preheat your oven to 350°F (177ºC) and line a large baking sheet with parchment paper or a silicone baking mat, setting it aside for use later.
- Mix Dry Ingredients: In a medium bowl, whisk together the all-purpose flour, crushed Biscoff cookies, cornstarch, baking soda, baking powder, and salt until well combined. Set this mixture aside.
- Cream Butter and Sugar: Using a handheld or stand mixer fitted with a paddle attachment, cream the softened unsalted butter and light brown sugar on medium-high speed for 2 to 3 minutes until light and fluffy. Then add the egg and vanilla extract, beating again until fully incorporated.
- Add Cookie Butter: Incorporate the Biscoff cookie butter into the creamed mixture, mixing until combined. Scrape down the sides and bottom of the bowl, then beat on low speed to ensure everything is well blended.
- Combine Dough: Gradually add the flour mixture while mixing on medium speed until no pockets of flour remain. Cover the dough and let it rest for 10 minutes.
- Shape Cookies: Using a cookie scoop, drop rounded balls of dough onto your prepared baking sheet. Roll each into a smooth ball with your hands. The dough should be soft but not sticky.
- Bake and Shape: Bake the cookies for 8 to 10 minutes until the edges are just set but the centers still look slightly underdone. While hot, quickly use a large round cookie cutter or the rim of a glass to reshape each cookie to uniform size and tuck in any thin edges. Let cookies rest on the baking sheet for 10 minutes before transferring them to a wire rack to cool completely.
- Melt Butterscotch Chips: Melt the butterscotch chips in a small saucepan over medium heat or in a microwave-safe bowl in the microwave until smooth. Set aside to cool for 10 minutes.
- Make Frosting: In a mixer bowl, combine the cooled butterscotch mixture with softened butter and marshmallow fluff. Beat on medium-high speed for 2 to 3 minutes until smooth. Add 1 tablespoon of water and blend to combine.
- Add Powdered Sugar and Salt: Lower mixer speed and slowly incorporate powdered sugar. Increase speed to medium and beat until fully combined and the frosting is creamy, scraping sides as needed. Add salt, taste, and adjust salt level if desired. Stir gently by hand with a spatula for 3 to 5 minutes to remove air bubbles and achieve a smooth consistency.
- Assemble Sandwich Cookies: Pair cookies of similar size, placing one bottom side up. Pipe or spread frosting on the bottom cookie, leaving a ½ inch border around the edges. Place the other cookie on top, gently pressing to spread frosting to the edges.
- Serving and Storage: Serve sandwiches immediately or let them sit for enhanced flavor. Store assembled sandwich cookies covered at room temperature for up to 5 days. Cookies and frosting can be made up to 2 days in advance and stored separately. Unbaked dough balls may be frozen for up to 3 months; thaw before baking as directed.
Notes
- Resting the cookie dough before baking improves texture and makes shaping easier.
- Reshaping hot cookies after baking ensures even size and prevents thin edges from burning.
- Frosting can be adjusted in sweetness and saltiness by varying the powdered sugar and salt amounts.
- Cookies achieve best flavor after sitting a while but can be enjoyed right away.
- Both assembled cookies and dough balls freeze well, making this recipe great for make-ahead baking and storage.
- Prep Time: 20 minutes
- Cook Time: 10 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American
