In a medium bowl, combine the flour, baking soda, and salt. Whisk together to mix well and set aside.

In the bowl of a stand mixer fitted with a paddle attachment, add the softened butter, granulated white sugar, and light brown sugar. Mix on high speed until fluffy and creamy, about 2 minutes.

Scrape down the sides of the bowl, then add the egg and vanilla extract to the butter-sugar mixture, and mix on medium speed until smooth.

With the mixer set to low speed, gradually incorporate the flour mixture, beating until just barely combined. Avoid overmixing.

Gently fold in the chopped Snickers, peanuts, chocolate chips, and chocolate chunks, ensuring even distribution throughout the dough.

Cover the bowl with plastic wrap and refrigerate the cookie dough for 30 minutes.

Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

Using a 1-inch cookie scoop, drop portions of dough onto the prepared baking sheet, spacing them about 2 inches apart.

Bake the cookies for 12-15 minutes, or until the edges are golden brown while the centers still appear slightly underdone.

Remove from the oven and let the cookies cool on the baking sheet for 5 minutes. Then transfer them to a wire rack to cool completely.