How to Make It
Preheat the oven to 350°. Line a 9-by-13-inch metal baking pan with parchment paper, leaving up to 1 inch of overhang. Spray the paper with vegetable oil spray.
In a medium saucepan, cook the butter over moderately high heat, stirring occasionally, until fragrant and browned, about 4 minutes. Scrape the butter into a large bowl and freeze just until solid, about 15 minutes.
Using a handheld electric mixer, beat the sugar, vanilla seeds and egg yolk into the butter at medium speed until blended. Add the flour and salt and beat until moistened crumbs form. Press the crumbs into the prepared baking pan and bake in the lower third of the oven for about 25 minutes, until the crust is set and lightly browned.
Meanwhile, wipe out the bowl used to make the crust. In a medium skillet, cook the bacon over moderately high heat until browned and crisp, about 5 minutes. Drain the bacon on paper towels and let cool. In the bowl, toss the coconut with the chocolate chips, almonds and bacon.
In another bowl, whisk the dulce de leche with the condensed milk; pour two-thirds of it in the crust. Lightly press the coconut-bacon mixture over the dulce de leche. Drizzle the remaining dulce de leche mixture on top.
Bake the bars for 35 to 40 minutes, until lightly browned on top. Transfer the pan to a rack and let the bars cool to room temperature, then refrigerate until firm, about 1 hour. Carefully remove the bars from the pan and peel off the paper. Cut into bars and serve.