Preheat the oven to 350°F and line an 8x8-inch baking pan with parchment paper, leaving overhang on two sides for easy lifting.
In a bowl, whisk the almond flour, protein powder and salt, then stir in the melted butter and maple syrup until a soft dough forms. Press it firmly and evenly into the bottom of the pan.
Bake for 14 to 16 minutes, until golden around the edges. Cool completely in the pan, as the shortbread firms up while it cools.
In a medium saucepan, combine the condensed coconut milk, butter, brown sugar and maple syrup over medium-low heat. Cook, stirring constantly with a heatproof spatula, for 10 to 12 minutes, until the caramel thickens, turns deep golden and pulls away from the sides of the pan.
Remove from the heat and stir in the almond butter, vanilla and salt until glossy. Pour over the cooled shortbread, spread evenly and refrigerate for 1 hour, until firm.
Melt the chocolate with the coconut oil in 30-second intervals, stirring until smooth. Pour it over the caramel, tilt the pan to spread it into a thin, even layer and sprinkle with flaky salt.
Chill for 30 minutes, until the chocolate is set. Let it sit at room temperature for 10 minutes before cutting into 16 squares, which keeps the chocolate from cracking.