"Three layers of rich goodness—buttery shortbread, gooey caramel, and a thick layer of dark chocolate—make up this well-healed dessert...."
confectioners’ sugar
(2 1/2 sticks) unsalted butter, at room temperature, divided
finely chopped, toasted slivered almonds
all-purpose flour, spooned and leveled
kosher salt, divided
(14-ounce) can sweetened condensed milk
packed dark brown sugar
pure honey
heavy cream, divided
pure vanilla extract
bittersweet chocolate, chopped
Flaky sea salt (such as Maldon), for garnish