Sift flour, baking soda and salt together in a small bowl. Set aside.
In a stand mixer on medium speed, beat butter, sugar, and brown sugar for 2 minutes. The mixture will lighten in color.
Add egg and vanilla and mix on medium speed for 1-2 minutes, until it looks like a buttercream. Scrap down the sides of the bowl occasionally.
Add flour mixture and stir (low speed on mixer) until just combined.
Stir in chocolate chunks and white rabbit candies.
Scoop approximately 2 tbsp. of cookie dough and place on a baking sheet lined with parchment paper. Leave roughly 1.5-2 inches between cookies. Optional: stick additional chocolate and candy pieces in each dough ball. Refrigerate for approximately one hour.
Preheat the oven to 350˚F. Bake the cookies for 12-15 minutes until the edges are golden brown and the center has lost that wet sheen look. I like baking one sheet at a time. If you bake multiple sheets, be sure to switch places and rotate sheets midway through baking.
The White Rabbit Candy will soften and melt at times creating a not-quite-round cookie. The candy melts and creates crispy edges. While the cookies are still warm just out of the oven you could take a glass and place it over each cookie and swirl thus smooshing the cookie into a round shape OR you could embrace the not-round look and enjoy the sweet crispy edges that look like lava flow off an island.
Transfer to a cooling rack and top with Maldon sea salt flakes if desired. Serve warm.