Preheat the oven to 350°F (175°C). Grease the 9x9 inch baking pan or line it with baking paper for easier removal.
In a mixing bowl, combine graham cracker crumbs, melted butter, and 2 tablespoons of sugar. Stir until well mixed and crumbly.
Press the graham cracker mixture firmly into the bottom of the prepared baking pan to form an even layer. Bake in the preheated oven for 8-10 minutes until golden. Remove and let it cool slightly.
In another mixing bowl, use an electric mixer (or whisk) to beat the softened cream cheese until smooth.
Add ½ cup sugar, eggs, vanilla extract, lemon zest, lemon juice, and salt to the cream cheese. Beat until well combined and smooth.
Pour the cream cheese mixture over the cooled graham cracker crust, spreading it evenly.
Bake in the oven for an additional 20-25 minutes, or until the center is set and a slight jiggle remains.
Let the bars cool to room temperature, then refrigerate for at least 2 hours before cutting into squares.
For serving, dust with powdered sugar if desired.