Spray a 9x13 inch pan with nonstick baking spray.

Place the butter in a large pot over medium heat. Let it melt and continue to bubble - you can swirl the pan a few times - until brown bits appear on the bottom of the pan. As soon as you see the bits, turn the heat down to low.

Immediately add 1 bag of the marshmallows. Another and ¼ of the second bag. Stir into the butter until the mixture is creamy and fully incorporated. You want all the marshmallows melted and the mixture to be gooey. Turn off the heat. Stir in the vanilla extract.

Add the cereal and mix with a large spatula. When the cereal is halfway mixed in, add the potato chips. Continue to mix and stir until the mixture comes together and the cereal and chips are equally distributed.

Add in the remaining marshmallows. Stir until they are incorporated so they are studded throughout the mixture. Press the rice krispy treat mixture into the prepared pan. I like to use a piece of wax or parchment paper to flatten and smooth out the top.

Melt the chocolate in the microwave. I do this in 30 second increments and stir after each. Once melted, drizzle over the rice krispy treats.

Once the chocolate sets, cut the treats into squares. Enjoy!