1-First, preheat your oven to 400ºF and line a baking sheet with parchment paper to avoid sticking and make cleanup easy. Next, arrange the 14 full graham cracker sheets evenly on the prepared baking sheet to create a solid base. In a saucepan, melt 1 cup of unsalted butter and 1 cup of lightly packed brown sugar over medium heat, stirring constantly until it bubbles and thickens into a smooth toffee mixture.

2-Pour the hot toffee mixture evenly over the graham cracker sheets, spreading it with a spatula for full coverage. Sprinkle 2 cups of semi-sweet chocolate chips over the top while it’s still warm, allowing them to melt slightly, and add ¼ cup of chopped nuts or optional toppings like chopped candy or sprinkles for extra flair. Bake in the preheated oven for 10-12 minutes until the toffee is bubbly and golden, then remove and let it cool completely at room temperature or in the fridge for about 30 to 60 minutes until it sets firmly.