Preheat the oven to 350 degrees F. Line a 12-cup cakecake pan with cupcake liners.
Add 3/4 cup unsalted butter and 3/4 cup brown sugar to a large mixing bowl. Use a hand mixer or a stand mixer on high speed to beat them together until fluffy.
Add 3 large eggs to the bowl and beat on high speed until light and fluffy.
In a smaller bowl, combine 1 cup flour and 1 1/4 teaspoon baking powder. Add it to the creamed mixture and beat it on low speed until the dry ingredients are just combined.
Divide the cupcake batter evenly between the cupcake liners.
Bake in the center of a preheated oven for 18 minutes or until the cupcakes have risen and are a pale golden brown. Set the cupcakes aside to cool completely.
Cupcake Filling
Gently warm the Biscoff spread in the microwave by brieflyl heating it just until it's a little runnier than usual.
Core the center of each cupcake and then add a teaspoon of the Biscoff spread in to each hole. (See notes below about center pieces of cupcakes.)
Frosting the Cupcake
Add the softened butter to the bowl and beat on a medium speed for 2-3 minutes until creamy.Then add the powdered sugar, half a cup at a time. Once all the powdered sugar has been added, beat on medium speed for a further 2 minutes.
Next, add the Biscoff spread to the mixing bowl, increase the speed to medium-high and beat for 5 more minutes.
Add the boiling water and beat on a low speed, this will change the buttercream to a smoother consistency.
Next, transfer the buttercream to a piping bag that's fitted with a star nozzle. Pipe buttercream swirls on top of each cupcake.
Warm the remaining Biscoff spread in the microwave for a few seconds or until it is pourable so you can drizzle the warm Biscoff spread over the top of the cupcakes then add Biscoff cookies on top of each cupcake.
Notes
Tips:
Bake to perfection: When properly baked, the cupcakes will have risen to the top of the cupcake liners, be a pale golden brown, and will spring back when gently touched with a finger.
Middle of cupcake: We didn’t replace the piece of cupcake we cut away as it can make the cupcake look a little lopsided. You can if you want to (or eat them!!).
Boiling water: Adding boiling water to the Biscoff buttercream helps smooth it out so that it almost looks the texture of a Swiss meringue buttercream. However, if you find the buttercream is too thin you can add the powdered sugar a tablespoon at a time. If it’s too thick, add extra boiling water a teaspoon at a time to reach the consistency that you need.
Piping tip: A Wilton 1M piping nozzle was used to frost these Lotus Biscoff cupcakes.
Storage: Store any leftover cupcakes in an airtight container in the refrigerator and enjoy within 3 days.