For the crust: Preheat the oven to 350 degrees. Grease an 8-inch square baking dish with coconut oil and dust with almond flour.
Combine the almond flour and salt in a food processor. Pulse in the coconut oil and stevia (see below) until thoroughly combined. Add in the zest and pulse a few times. The crust will not form a ball, so do not worry when it looks just like it did when you put it in the processor.
Dump the mixture into the baking dish and press the dough into the bottom. Bake the crust 12 to 17 minutes, until slightly golden brown. While the crust bakes, prepare the topping.
To make the key lime batter: In a high powered blender or regular blender (I used mine on "ice crush" option to enhance the speed), puree the lime juice, eggs, coconut oil, honey and zest until smooth.
When the crust is ready, remove it from the oven. Whirl the topping a few more times in the blender to make sure everything is still well mixed and then carefully pour the topping over the hot crust.
Return the baking dish to the oven and bake for 18 to 22 minutes, until the topping is golden. Let the bars cool in the dish for 30 minutes and then refrigerate for 2 hours so it sets.
Cut into 12 squares and serve. I added a few squirts of whipped cream and the zest of a lime for garnish.
Store covered in the fridge for up to 2 days.