Prepare Your Pan and Oven Preheat the oven and line an 8x8-inch square baking pan with parchment paper, leaving a slight overhang on the sides for easy removal.

Cream the Butter and Sugar Using a mixer, beat the softened butter and granulated sugar together on medium-high speed until the mixture is light, fluffy, and pale in color.

Add the Wet Ingredients Lower the speed and incorporate the eggs one at a time, followed by the vanilla extract, scraping down the sides of the bowl to ensure a thorough mix.

Mix in the Dry Ingredients Add the flour, sea salt, and baking soda, mixing on low speed until the dough just begins to clump together without over-working it.

Chill the Dough Wrap the dough and let it rest in the refrigerator to firm up, making it easier to handle and layer.

Create the First Layer Press half of the chilled dough evenly into the bottom of the pan, then lift it out using the parchment and place it in the freezer briefly to set.

Assemble the Bottom and Filling Press the remaining dough into the bottom of the lined pan and spread the strawberry preserves over it, leaving a small border around the edges.

Add the Top Layer Place the chilled top layer of dough over the preserves and gently press the edges to seal the filling inside.

Bake to Perfection Bake until the top is a light golden brown, then remove from the oven and allow the bars to cool completely in the pan.

Glaze and Finish Whisk together the powdered sugar, milk, and vanilla to create a smooth glaze. Flip the cooled bars for a flat surface, spread the icing on top, add sprinkles, and let set before slicing.