• Turn your oven on to 350°F (or 177°C).

Crust

• Grab a medium bowl and toss in your graham cracker crumbs (1 ½ cups of graham cracker crumbs and ¼ cups of sugar. Stir in 6 tablespoons of melted butter until the mixture looks thick and sandy.
• Pour this mixture into a 9" pie dish (no need to grease). Press the mixture down to create an even base and push it up the dish's sides to form a crust.

Brownie Batter

• Cut your butter into a few tablespoon-sized chunks and melt it in a big, heatproof bowl on the stove or in the microwave. Add 2 tablespoons of oil and 1 cup of sugar and give it all a good whisk. Let the mixture sit for a couple of minutes to cool down just a bit.
• Whisk in two whole eggs, one extra yolk, and 2 teaspoons of vanilla extract 'til mixed. Add in ½ cup of flour, ¾ cup of cocoa powder, and ¼ teaspoon of salt, and whisk again until blended.
• Gently fold in some semi-sweet chocolate chips.

Baking and Toasting

• Bake for about 30 minutes. Take the pie out and top it with gooey marshmallows, then lightly press them down so they stay put without getting smushed.
• Put the pie back into your oven for another 3-4 minutes to let the marshmallows toast up.
• Want them a bit more golden? Switch the oven to broil for 30 to 60 seconds, keeping your eyes on them to prevent burning.

Serving

• Let the pie cool on a wire rack for 45 minutes to 2.5 hours (or even more until fully set).
• To make slicing a breeze, run a sharp knife beneath hot water, dry it off, and cut. Enjoy every bite!