Preheat oven to 350°F (180°C). Line 8x8” pan with foil or parchment and spray with cooking spray.

In a large bowl, combine melted butter and sugar. Once sugar has dissolved, add eggs and vanilla, whisking until smooth.

In a separate bowl, whisk together flour, baking powder, and salt.

Pour dry mixture into wet mixture, mixing to integrate. Stir in white chocolate chips and pretzels, or mix-ins of choice.

Pour batter into prepared pan and smooth into an even layer.

Bake 20-25 minutes, until edges brown but middle still looks slightly underdone. Check to make sure a toothpick comes out clean.

Near end of bake time, make date caramel (see below). Drizzle caramel onto blondies when they come out of the oven. (I use a squeeze bottle for this!)

Allow to cool completely before cutting.

Combine everything in a food processor and blend until smooth, about 3 minutes. Add milk as needed to smooth out.

Use immediately or store in the fridge for later.