Ingredients
Equipment
Method
- Set oven rack to middle position and preheat to 325°F (165°C). Line a 9×9 inch (23×23cm) light-colored aluminum pan with parchment paper leaving a 2-inch overhang on all four sides.
- In a large bowl using a hand mixer or stand mixer fitted with the paddle attachment, beat 1 cup (226g) softened unsalted butter on medium speed for 60 seconds until smooth. Add ¾ cup (150g) granulated sugar and ¾ cup (165g) packed brown sugar and beat on medium speed for exactly 3 minutes until pale and slightly fluffy.
- Add 2 large room-temperature eggs one at a time on low speed, mixing for 20 seconds after each and scraping the bowl between additions. Add 1 teaspoon (5ml) pure vanilla extract with the second egg.
- In a separate bowl whisk together 2¼ cups (270g) all-purpose flour, 1 teaspoon (6g) baking soda, and 1 teaspoon (6g) fine sea salt. Add the flour mixture to the butter mixture in two additions on the lowest speed, mixing only until the last streak of flour disappears after each addition.
- Remove bowl from mixer and fold in 1½ cups (255g) semi-sweet chocolate chips by hand using a silicone spatula with approximately 15 strokes. Weigh the full dough batch and divide — transfer two-thirds (approximately 680–700g) to the lined pan and keep the remaining one-third (approximately 340–350g) in the bowl. Set aside a small extra handful of chips (approximately 2 tablespoons / 30g) separately — these go on top of the assembled bars before baking.
- Press the two-thirds dough portion firmly and evenly across the bottom of the pan using your fingers and the flat bottom of a measuring cup, pressing into the corners until completely flat and uniform.
- In a clean bowl beat 16 oz (452g) full-fat block cream cheese on medium speed for 90 seconds, scraping the bowl at 45 seconds, until completely smooth with no lumps. Add ½ cup (100g) granulated sugar and beat 30 seconds. Add 1 large room-temperature egg and 1 teaspoon (5ml) pure vanilla extract on the lowest speed and mix only until the egg disappears — approximately 15 to 20 seconds. Fold in ½ cup (85g) semi-sweet chocolate chips by hand.
- Pour the cheesecake filling over the pressed cookie base and spread evenly to the edges with a silicone spatula. Tear the reserved one-third cookie dough into rough tablespoon-sized pieces and drop them across the surface in an irregular patchwork pattern, leaving 30–40% of the cheesecake surface exposed between pieces. Press the reserved extra 2 tablespoons (30g) of semi-sweet chocolate chips across the top of the dough pieces and into any exposed cheesecake.
- Bake on the middle rack at 325°F (165°C) for 35 to 40 minutes, until the cookie topping pieces are golden brown, the cheesecake edges are set and slightly puffed, and the center has a 2-inch uniform jiggle when the pan is gently shaken. Do not open the oven before 30 minutes.
- Remove from oven and place on a wire rack. Cool at room temperature for exactly 2 hours — do not refrigerate during this time. Transfer to the refrigerator uncovered and chill for a minimum of 2 hours, preferably overnight.
- Lift the slab from the pan using the parchment overhang and place on a cutting board. Wipe a sharp knife clean with a damp cloth between every cut and slice into a 3×4 grid for 12 bars. Serve cold.
Notes
Full-fat block cream cheese only — low-fat or whipped versions will not set correctly and produce a wet, loose filling that cannot be sliced.
Pull cream cheese from fridge 60–120 minutes before starting — do not microwave to soften. Cold cream cheese produces permanent lumps that baking cannot fix.
Butter must be softened to 65–68°F (18–20°C) — press your finger in and it should indent cleanly without feeling greasy or slick.
Weigh the dough division — two-thirds base / one-third topping. A base built from less than two-thirds will crack when the slab is lifted from the pan.
Do not cut before completing the full cooling sequence — 2 hours room temperature followed by minimum 2 hours refrigerated. Cutting early collapses the cheesecake layer.
Baking soda freshness test: drop ½ tsp into hot water with a splash of white vinegar — aggressive bubbling in 2 seconds means it is active.
Dark pans: reduce oven temperature to 300°F (150°C) and add 5 minutes to bake time.
High altitude (above 3,500ft / 1,067m): reduce baking soda to ¾ tsp (4.5g), add 2 tbsp (15g) flour, increase oven temp to 340°F (170°C).
Allergens: contains wheat, eggs, dairy, soy (in most chocolate chip brands).
Freeze baked bars individually wrapped up to 2 months — thaw overnight in refrigerator only.
Make-ahead: best made the day before — Day 2 texture and flavor is noticeably better than Day 1.