Preheat the oven to 350 degrees F. Line a baking sheet with a silicone baking mat or parchment paper. Combine the almond flour, all-purpose flour and salt in a large bowl; set aside. Combine the sugar, heavy cream, corn syrup and butter in a small saucepan and cook over medium heat, stirring occasionally, until the mixture comes to a boil and the sugar is dissolved; continue to boil 1 more minute. Remove from the heat and stir in the vanilla. Pour the sugar mixture into the flour mixture and stir until just combined. Set aside until cool enough to handle, about 30 minutes.
Roll rounded tablespoonfuls of dough into balls. Arrange at least 3 inches apart on the prepared baking sheet. Bake, rotating the baking sheet halfway through, until the cookies spread out and turn golden brown, 10 to 11 minutes. Let cool 5 minutes on the baking sheet, then transfer to a rack to cool completely. Repeat with the remaining dough.
Make the glaze: Microwave the semisweet chocolate and white chocolate in separate microwave-safe bowls in 30-second intervals, stirring, until smooth. Transfer the white chocolate to a small resealable bag. Flip the cookies over so the smooth side is up. Spread each cookie with a thin layer of semisweet chocolate. Snip a corner of the white chocolate bag and pipe lines on the semisweet chocolate; drag a toothpick across the lines. Let set, about 2 hours.
Photograph by Ryan Dausch