1. Preheat the oven to 350°F (175°C). Line a 9×13 inch baking pan with parchment paper, leaving some overhang on the long sides for easy removal, and lightly grease the parchment.

2. In a large mixing bowl, beat the softened butter and granulated sugar together with a hand mixer or stand mixer on medium speed until light, creamy, and slightly fluffy, about 3 to 4 minutes.

3. Add the eggs one at a time, mixing well after each addition. Beat in the vanilla extract and almond extract until the mixture is smooth and fragrant.

4. In a separate bowl, whisk together the all purpose flour, cornstarch, baking powder, and fine sea salt until well combined.

5. Add the dry ingredients to the butter mixture in two additions, mixing on low speed just until no dry streaks of flour remain. The dough will be thick, similar to soft sugar cookie dough.

6. Press the dough evenly into the prepared pan, smoothing the top and pushing it gently into the corners with clean hands or an offset spatula.

7. Bake for 18 to 22 minutes, or until the edges are lightly golden and the center looks set but not browned. Do not overbake. Remove the pan from the oven and let the bars cool completely on a wire rack.

8. Once the bars are cool, make the frosting. In a medium bowl, beat the softened butter until smooth. Gradually add the powdered sugar, mixing on low at first so it doesn’t puff out of the bowl.

9. Add the heavy cream or milk, vanilla extract, almond extract, and a pinch of salt. Beat on medium-high speed until the frosting is light and fluffy, 2 to 3 minutes, adding a tiny splash more cream if needed for a spreadable consistency.

10. Tint the frosting with 2 to 3 drops of pink gel food coloring, mixing until the color is evenly distributed and you reach your desired Valentine’s Day shade.

11. Spread the pink frosting over the cooled sugar cookie bars in an even layer, swirling the top with an offset spatula. Immediately add the Valentine sprinkles so they stick to the soft frosting.

12. Lift the frosted slab out of the pan using the parchment overhang and transfer it to a cutting board. Slice into 16 large bars or smaller squares as desired, wiping the knife between cuts for clean edges. Serve at room temperature.