Preheat your oven to 350 degrees F and line an 8-inch square baking dish with parchment paper. This ensures easy removal later and helps to prevent sticking.
In a medium bowl, take your softened cream cheese, granulated sugar, and all-purpose flour. Using a hand-held electric mixer, beat the mixture until it’s smooth and creamy. Once combined, beat in one egg and vanilla extract until just mixed in. Set this creamy filling aside; it’s going to be the heart of your bars.
In another clean mixing bowl, beat together the unsalted butter, light brown sugar, and the remaining granulated sugar until it’s light and fluffy. This should take about 4 minutes. The texture should be airy, which will help create a lovely bar.
With your mixer set to low, beat in the remaining egg just until it’s combined with the mixture.
In a medium bowl, whisk together 2 cups of all-purpose flour, ¾ teaspoon salt, ½ teaspoon baking powder, ½ teaspoon baking soda, ½ teaspoon cinnamon, and ¼ teaspoon ground nutmeg. This blend of dry ingredients will give the bars their structure and flavor.
Gradually add the dry flour mixture into the butter mixture while the mixer is still on low. Mix until just combined; you don’t want to over-mix here.
Now, fold in the grated zucchini and mini chocolate chips. Mix on low just until everything is evenly distributed. You’ll notice the batter becoming rich and thick.
Transfer a little over half of the batter to the prepared baking pan, spreading it evenly across the bottom. This will form the base layer.
Next, take the cheesecake mixture you made earlier and spread it evenly over the batter base. Make sure it’s well distributed across the surface.
Spoon the remaining batter over the cheesecake layer, spreading it out gently. It doesn’t need to be perfect; the layers will meld together beautifully as they bake.
Place the pan in the preheated oven and bake for 40 to 45 minutes. Check on them at the 30-minute mark; if the top is browning too much, cover it with foil. The top may look done after 40 minutes, but ensure the top layer of batter is fully cooked underneath by inserting a toothpick.
Once baked, allow the bars to cool completely before cutting them into squares. For an extra treat, I recommend refrigerating them first; it makes every bite refreshingly cool!
