1/3 cup granulated sugar
2 tablespoons unsalted butter
Flaky sea salt
2 tablespoons heavy cream
8 tablespoons (4 ounces or 115 grams) unsalted butter
3/4 cup light or dark brown sugar
1 large egg
1 teaspoon vanilla extract
1/2 teaspoon flaky sea salt, or 1/4 teaspoon coarse sea salt
1 cup (130 grams) all-purpose flour
2/3 cup dark chocolate chips or chunks
1/2 cup thin salted pretzels, lightly crumbled
Make caramel: Cover a medium-sized plate or small tray with parchment paper. Lightly butter or coat the parchment with a spray oil, just as an added security measure.
In a medium, dry saucepan over medium heat, melt your sugar; this took me exactly 4 minutes ever single time. By the time it is mostly melted, if should be a nice deep copper color (about 300°F to 325°F, but you do not need a thermometer to get the color right at this stage) and might smoke a little too, don’t worry. Tip and swirl the pan around to help even it out and melt any remaining sugar granules.
Remove pan from heat and whisk in butter until melted, then add a couple pinches of salt and cream, whisking until combined. Return pan to the stove over medium-high heat and cook without stirring for 3 minutes more, at which point it should be between 245°F and 250°F (the “firm ball” stage). If you don’t have a thermometer, the temperature is correct when a drop that lands in cold water will hold its shape but still be sticky when pressed with your fingers. Pour this caramel on to the prepared parchment and place in the freezer until needed. It will take 10 to 15 minutes to firm enough that it can be cut into squares.
Make blondies: Heat your oven to 350°F. Butter an 8×8-inch baking pan, or line the bottom and two sides of one with parchment paper, buttering the exposed parts. Melt butter about 2/3 of the way in the bottom of a large bowl, either over a double-boiler or in the microwave. Stir to melt the remaining 1/3 — this ensures the butter doesn’t get too hot to work with. Add sugar and whisk to combine, then egg, vanilla, and sea salt. Add flour and stir just until it disappears. Scattered chocolate chips and pretzels on batter. Remove caramel from freezer and cut quickly into 1-inch squares. Scatter all but 4 to 5 over bowl. Gently fold chunky ingredients into batter and spread in prepared baking pan, smoothing the top. Place remaining caramel squares on top.
Bake for 25 to 30 minutes, or until deeply golden at edges and mostly dry on top. [For a swirlier effect, drag a toothpick through a couple of the caramels on top about 15 minutes in.] Let cool in pan for 10 minutes before lifting blondies out by their parchment sling and cooling further on a rack. Cut into small squares and simply marvel at how popular you are.
Do ahead: These keep at room temperature for 3 days, and a week or more in the fridge.
If you’d like to ship them out: Freeze them and then pack them into your most snug, airtight container with layers of parchment paper between them. Wrap the top in plastic before putting the lid on. I sometimes go one step further and wrap the whole container in foil. Pack with peanuts or another filler in a larger box and choose the fastest shipping you can.