Break chocolate chip cookies into varied sizes—some fine crumbs and some pea-sized chunks—to ensure even texture distribution throughout your fudge without creating dense pockets.

Pour half the fudge mixture into your prepared pan, sprinkle cookie pieces and mini chips on top, then add the remaining fudge to create a perfectly distributed interior rather than settling everything at the bottom.

Let your sweetened condensed milk and butter mixture cool to 110°F before folding in chocolate chips to prevent the chips from melting into the fudge, keeping them distinct for better texture.

Add vanilla extract in the final seconds of mixing after all ingredients are combined—this preserves its delicate flavor notes that heat can diminish, enhancing the overall complexity of your fudge.

Refrigerate for at least 4 hours, then use a hot, wet knife (wiped between cuts) to slice cleanly without the fudge cracking or sticking, and store in an airtight container with parchment between layers.