Preheat your oven to 350°F (175°C) and lightly grease your 9x9 inch baking pan or line it with parchment paper for easier removal.
In a mixing bowl, whisk together the flour, salt, baking soda, and baking powder. Set this mixture aside for later.
In a separate large bowl, cream the room-temperature butter, granulated sugar, and brown sugar until the mixture is light and fluffy, about 3-4 minutes with an electric mixer.
Add the egg yolk and vanilla extract to the butter mixture, mixing until well combined.
Gradually add the dry ingredients to the wet ingredients, mixing just until combined. Be careful not to overmix.
Gently fold in the semisweet chocolate chips, ensuring they are evenly distributed throughout the batter.
Spread the batter evenly into the prepared baking pan. Bake in the preheated oven for about 20-25 minutes, or until the edges are golden and a toothpick inserted into the center comes out clean.
While the base is baking, make the meringue. In a clean mixing bowl, beat the egg white with an electric mixer until soft peaks form. Gradually add the 1/4 cup brown sugar, continuing to beat until stiff peaks form and the mixture is glossy.
Add the tablespoon of water to the meringue and mix until fully incorporated.
Once the chocolate chip base is done baking, remove it from the oven and immediately spread the meringue over the warm bars. Make sure to spread it all the way to the edges to prevent shrinking.
Return the pan to the oven and bake for an additional 10-15 minutes, or until the meringue is lightly golden.
Allow the bars to cool completely in the pan on a wire rack. Once cooled, slice into squares and serve!