Add the eggs and beat on medium speed, making sure that the first egg is fully incorporated before adding the second. Add the vanilla and almond extracts and beat for 30 seconds. Stop the mixer and scrape down the sides of the bowl and the paddle.

Turn the mixer to low speed and slowly add the flour mixture. Stop mixing when the flour is completely incorporated. Remove the bowl from the mixer. Add the sprinkles and stir with a stiff spatula until evenly distributed.

Transfer the dough into the prepared baking pan and spread into an even layer with wet fingers or an offset spatula. Bake until golden-brown around the edges and light brown across the top, 20 to 25 minutes.

Place the pan on a wire rack and cool for 10 minutes. Use the parchment sling to lift the cookie slab out of the pan, and then place the slab on the wire rack to cool completely. While the cookie slab cools, make the frosting.

Make the frosting: Place the butter and salt in a clean bowl of a stand mixer fitted with the paddle attachment. (Alternatively, use an electric hand mixer and large bowl.) Beat on medium speed until lightened in color and creamy, about 3 minutes. Scrape down the sides of the bowl as needed.

Turn the mixer to low speed and add the powdered sugar, 1 cup at a time, until incorporated. With the mixer still running, add the vanilla extract, almond extract and cream. Increase the speed to medium and beat until smooth and creamy, about 2 minutes. Remove the bowl from the mixer, and fold in the sprinkles. Cover with a clean, damp towel until ready to use. If the frosting starts to dry and develop a crust, simply beat again with the mixer until creamy.

Once the cookie slab has cooled, scoop the frosting onto the slab and use an offset spatula to spread into an even layer. Top with additional sprinkles if desired. Let sit at room temperature for at least 30 minutes to let the frosting form a crust. Trim the edges of the slab if desired, then slice into 24 bars.

Recipe notes: The frosting can be made up to one week in advance and refrigerated. Let come to room temperature and beat until creamy before using. Store leftovers in an airtight container at room temperature for up to three days, or wrap them in foil and freeze for up to three months. Thaw at room temperature before serving.

(Patty Catalano is a contributor to TheKitchn.com, a nationally known blog for people who love food and home cooking. Submit any comments or questions to editorial@thekitchn.com.)