Tender Biscoff cake layers, filled with a creamy Biscoff cookie spread, Biscoff cookies, covered with a white chocolate frosting.
In a microwave safe bowl, heat the cream and then pour it over the white chocolate to melt. Stir until the mixture is smooth and silky. If needed heat the mixture for another 20 to 30 seconds and stir until the chips are melted. Set aside.
Slowly add the white chocolate (which should still be warm) while mixing on medium-low speed. Using warm white chocolate will soften your butter but is important because it won't harden when it hits the cold butter like room temperature white chocolate will. If your buttercream feels soft after it's all mixed, just refrigerate the buttercream to harden it just a bit.
Add the vanilla and increase the speed to medium-high and beat the frosting for five minutes, until light in color and texture.