Preheat your oven to 350°F (175°C) and grease a 9×13 inch baking dish.

In a mixing bowl, combine graham cracker crumbs, melted butter, and sugar until the mixture resembles wet sand.

Press this mixture evenly into the prepared baking dish and bake for 8-10 minutes until lightly golden.

Remove from the oven and set aside to cool.

In a large mixing bowl, beat together the granulated sugar, brown sugar, eggs, and vanilla extract until well combined.

Stir in the grated carrots.

In another bowl, whisk together flour, baking powder, baking soda, cinnamon, nutmeg, and salt.

Gradually add the dry ingredients to the wet mixture, and fold in walnuts if using.

Spoon this batter onto the cooled crust and spread evenly.

Using an electric mixer, beat the softened cream cheese, granulated sugar, eggs, and vanilla extract until smooth.

Carefully pour this cheesecake mixture over the carrot cake layer, spreading evenly with a spatula.

Bake in the preheated oven for 30-35 minutes until the edges start to brown slightly and the center is set.

Allow the bars to cool completely in the baking dish before slicing into squares.

Once cooled, slice into bars, and serve with a dusting of powdered sugar or a drizzle of cream cheese frosting if desired.