The Kirkland Signature Hazelnut Mousse Bar Cake is a rectangular layered dessert from Costco's bakery, featuring alternating strata of moist chocolate cake and silky hazelnut mousse filling. The exterior is finished with a glossy chocolate glaze and decorated with dark and white chocolate curls and swirls, giving it an elegant appearance.

Part of Costco's popular rotating bar cake lineup, this refrigerated dessert weighs approximately 2.5 pounds and is designed to serve up to 20 slices. The hazelnut mousse layers provide a light, airy contrast to the denser cake layers, while the rich chocolate coating ties all the components together. The bar format makes it easy to slice and serve at gatherings, and the refrigerated shelf life of 10 or more days ensures it stays fresh throughout extended entertaining.