Use a slightly underbaked, fudgy brownie base so the pretzels don't make it cakey. Toss pretzel pieces in a small amount of melted butter and a sprinkle of sugar before pressing some into the top of the batter — this helps them stay crisp after baking. For the caramel, cook sugar until amber, add cream and a pinch of flaky sea salt. Drizzle lightly to keep the balance between sweet and salty.
Pro Tip
If you want extra crunch on serving day, reserve a handful of pretzel pieces to scatter over the caramel just before presenting.