Preheat your oven to 175°C (350°F). Line a 9-inch square baking pan with parchment paper, leaving overhang on the sides for easy removal.
Combine the graham cracker crumbs, melted butter, and salt in a bowl. Mix until the crumbs are evenly coated and resemble wet sand.
Press the crumb mixture firmly into the bottom of the prepared pan to form an even crust. Use the back of a spatula or your fingers to smooth it out.
Bake the crust for 10 minutes until golden and fragrant. Remove from the oven and set aside to cool slightly.
In a large mixing bowl, beat the softened cream cheese and sugar with an electric mixer until smooth and creamy, about 2-3 minutes. This creates a fluffy base for the filling.
Add the eggs one at a time, mixing well after each addition to ensure a smooth batter.
Stir in the pumpkin puree, cinnamon, nutmeg, cloves, and vanilla extract until well combined. The mixture should be smooth and slightly thickened.
Pour the pumpkin filling over the baked crust, spreading it evenly with a spatula so the surface is smooth and level.
Bake the assembled bars for 40-45 minutes, until the edges are lightly browned and the center jiggles just slightly when gently shaken.
Remove the pan from the oven and let the bars cool in the pan for about 30 minutes. Then, refrigerate for at least 4 hours or overnight to set fully.
Lift the bars out of the pan using the parchment overhang. Slice into squares and serve chilled, optionally garnished with whipped cream or toasted pecans for extra flair.