1.Prep the Pan: Preheat your oven to 350°F (175°C). Line a 9×13-inch metal baking pan with parchment paper, leaving an inch of overhang on the sides to use as a “handle” later.

2. Make the Crust: In a medium bowl, combine the crushed pretzels, melted butter, and sugar. Stir until the pretzels are evenly coated. Press the mixture firmly into the bottom of the prepared pan. Bake for 8–10 minutes until just set. Remove from the oven and let cool slightly.

3. Make the “One-Pot” Caramel: In a medium heavy-bottomed saucepan, melt the 1 cup of butter over medium heat. Whisk in the brown sugar, sweetened condensed milk, and fine sea salt. Bring the mixture to a gentle boil, whisking constantly. Once it reaches a boil, reduce the heat to medium-low and simmer for 5 minutes, whisking continuously to prevent burning. The caramel should be thick, smooth, and amber-colored.

4. The Pour: Remove the caramel from the heat and stir in the vanilla extract. Immediately pour the hot caramel over the pretzel crust, spreading it to the edges with a spatula.

5. Chill and Garnish: While the caramel is still warm, sprinkle generously with flaky sea salt. Let the bars cool at room temperature for 30 minutes, then transfer to the refrigerator for at least 4 hours (or overnight) to set completely.

6. The Clean Cut: Once the caramel is firm, lift the bars out of the pan using the parchment handles. Use a sharp, warm knife to cut into squares, wiping the blade clean between each cut.