Preheat the oven to 350ºF.
Line an 9x13 inch baking pan with parchment paper. Set aside.
In a large bowl, cream together the butter and sugar until fully combined. Add in the eggs and vanilla until fully incorporated.
Mix in the flour and salt until just combined. Fold in the chocolate chips.
Pour the batter into the prepared baking pan. Top with the pretzels (4x6), and bake for 35-40 minutes.
Remove from oven, and allow to cool completely. Cut into squares.
In a small bowl, add the dark chocolate chips and coconut oil. Heat in the microwave for 30 second intervals, mixing after each interval until smooth.
Drizzle the melted chocolate over the squares. Place in the fridge until the chocolate hardens.