Put the cereal into a large bowl. Melt the white chocolate chips and shortening in the microwave, or you can use a double boiler for the same results. Pour the melted chocolate over the cereal and stir together until the cereal’s evenly coated.

Pour the coated cereal out onto a piece of parchment paper, gently spreading it out so its not a giant pile, but not necessarily an even layer either. Let the coated cereal sit, about 20-30 minutes, to allow the chocolate to harden.

In a large skillet over medium heat, add the butter to melt. Watching constantly and stirring occasionally let the butter melt until it becomes golden brown and smells nutty. Again keep a close eye as it can go from browned to burnt in an instant. Remove the skillet from heat and allow it to cool completely.

In a large bowl stir together the flour, baking soda, and salt. In a separate bowl briskly whisk together the egg, egg yolk, milk, and vanilla until smooth. To the bowl of a stand mixer add the cooled butter, sugar and brown sugar. Using the paddle attachment, beat the mixture on medium speed for 2 minutes. Slowly pour the egg mixture into the bowl, mixing until just combined. Slowly add in the dry ingredients, mixing just until they're evenly come together ina batter. Use a firm spatula to stir in the Fruity Pebble crunch and the marshmallow bits just until evenly incorporated.

Use a small scoop to place about 2 tablespoons of cookie dough onto a cookie sheet, each about 2 inches apart. Bake the cookies at 350 degrees for 10 minutes. Let the cookies rest a minute or two and then transfer to wire racks to finish cooling completely.

Serve warm with a glass of milk.