Line an 8×8 inch square baking pan with parchment paper, leaving an overhang on two sides for easy removal.
In a medium bowl, combine graham cracker crumbs, melted butter, granulated sugar, and 1/4 teaspoon salt. Stir until the mixture resembles wet sand.
Press the graham cracker mixture evenly into the bottom of the prepared pan to form the crust. Set aside.
In a large bowl, beat the softened butter, light brown sugar, and granulated sugar together with an electric mixer on medium speed until creamy and smooth, about 2-3 minutes.
Add vanilla extract and mix to combine.
In a separate bowl, whisk together all-purpose flour and 1/2 teaspoon salt.
Gradually add the flour mixture to the butter mixture, mixing on low speed until just combined. The dough will be thick.
Fold in the mini semisweet chocolate chips and semisweet chocolate chips evenly.
Spread the cookie dough evenly over the graham cracker crust in the pan, pressing gently to smooth the top.
Refrigerate the bars for at least 2 hours or until firm.
Use the parchment paper overhang to lift the bars out of the pan. Cut into 12 equal squares and serve.