Melt the butter in a medium saucepan over medium-high heat, stirring occasionally until fully melted (3-5 minutes).

Combine with sugar: After the butter melts, add granulated sugar and stir until dissolved (2 minutes).

Bring to a boil, stirring constantly for about 10-15 minutes until the mixture is medium tan color.

Prepare the cookie sheet by lining it with parchment paper and distribute any optional chopped nuts if using.

Pour the toffee mixture over the prepared nuts, spread evenly using a spatula.

Add chocolate chips over the still-warm toffee and let them melt before spreading evenly.

Optionally, sprinkle additional chopped nuts or sprinkles over the chocolate layer.

Cool completely for a couple of hours before breaking into pieces.