In a large mixing bowl, beat the softened cream cheese and unsalted butter together until creamy and well combined, using a hand mixer or stand mixer on medium speed.
Gradually add in the brown sugar and granulated sugar, mixing until the mixture is light and fluffy.
Pour in the vanilla extract and salt, and mix until fully incorporated.
Add the all-purpose flour to the mixing bowl, and mix on low speed until the flour is fully combined into the dip.
Gently fold in the mini chocolate chips and crushed walnuts or pecans if using, until evenly distributed.
Transfer the dip to a serving bowl and cover with plastic wrap. Chill in the refrigerator for at least 30 minutes to allow the flavors to meld.
Serve cold with an assortment of dippers like graham crackers, pretzels, apple slices, or cookies.
Notes
Serve the dip in a pretty bowl with a drizzle of melted chocolate on top and sprinkle extra mini chocolate chips around the edges for a decorative touch.