Preparation

• Line a baking sheet with parchment and lightly spray with nonstick cooking spray.

• In a saucepan over medium heat, combine the butter, sugar, bourbon, vanilla and kosher salt. Let the butter melt and sugar dissolve, then increase the heat to medium-high and bring to a boil, stirring constantly with a whisk until the mixture turns a dark amber and is thick, 12 to 15 minutes. (To use a candy thermometer for this step, attach it to the saucepan and cook until the temperature reaches 285 degrees.)

• Pour the toffee mixture onto the prepared baking sheet and immediately sprinkle the chocolate chips evenly over the top. Let sit 2 minutes so the chocolate begins to melt, then spread the chocolate with an offset spatula to create a layer on top of the toffee. Sprinkle the almonds, pecans and flaky sea salt evenly over the top. Refrigerate until set, about 1 hour, then cut or break into pieces.