In a large bowl (I used my stand mixer), add the butter, sugar, brown sugar, and vanilla. Beat until creamy.
2 sticks butter, 3/4 cup sugar, 3/4 cup packed brown sugar, 1 teaspoon vanilla extract
Add in the eggs, one at a time, beating well after each one.
2 eggs
Gradually beat in the flour mixture - I do it in thirds.
Stir in the crushed pretzels.
1 cup crushed dark chocolate covered pretzel thins
Spread the dough evenly into the jelly roll pan.
Bake for 20-25 minutes or until golden brown.
While the bars were baking, I took the remaining dough and scooped out 6 cookies onto a baking sheet lined with parchment paper. Once the bars were done, I baked the cookies for about 9 minutes until the edges were golden brown.
Notes
Makes about 15 bars + 6 cookies (depending on how generous you cut them)
I prefer using salted butter in baking, but for these bars, I use a combination of 1 stick salted and 1 stick unsalted to balance the saltiness from the pretzels.