Step 1: Preheat your oven to 350°F (175°C).
Step 2: Line a rimmed baking sheet with parchment paper.
Step 3: Place the graham cracker sheets in a single layer on the prepared baking sheet.
Step 4: In a medium saucepan over medium heat, combine the unsalted butter and light brown sugar. Stir until boiling and allow it to boil for 3-4 minutes without stirring.
Step 5: Immediately pour the hot toffee mixture over the graham crackers, spreading it evenly.
Step 6: Bake for about 5-7 minutes, until bubbly and caramelized.
Step 7: Remove from the oven and dollop peanut butter over the hot toffee, spreading it evenly.
Step 8: Melt the semi-sweet chocolate chips until smooth and drizzle over the peanut butter layer.
Step 9: Sprinkle chopped roasted peanuts on top and press gently to adhere.
Step 10: Allow to cool at room temperature for about an hour, then refrigerate until set completely.
Step 11: Lift the toffee out using parchment paper and cut into squares or rectangles.