When I first tried making this giant gooey cookie with a frozen Nutella center, I was amazed at how easy it was to create a bakery-style dessert right at home. The secret is freezing the Nutella beforehand so it stays perfectly molten after baking. I recommend dividing the dough evenly to ensure each cookie contains a generous Nutella core, and using quality chocolate chunks enhances the gooey chocolate texture. Baking it at 170°C (338°F) for exactly 15 minutes plus 3 minutes under top heat gives the cookie a crisp golden exterior while keeping the center delightfully soft and wobbly. One tip I learned is to let the cookie rest for about 10 minutes before digging in; this helps the molten center settle slightly and prevents burning your mouth. This giant cookie makes a fantastic dessert for gatherings or a cozy treat to share. Pair it with a cold glass of milk or a scoop of vanilla ice cream for an indulgent experience. Additionally, you can experiment by swapping Nutella with other frozen spreads like peanut butter or caramel for varied gooey centers. Overall, this recipe proved to be a fun and rewarding baking project that is approachable even for beginners. The combination of brown and white sugar balances sweetness and chewiness, while the baking soda and salt contribute to that classic chocolate chip cookie rise and flavor complexity. If you're someone who loves experimenting with baking or is a Nutella fan, this giant molten center cookie is a delightful recipe to add to your repertoire.