Preheat the oven to 350 degrees Fahrenheit and line a shallow oven tray with baking paper. Add the peanut butter, erythritol, desiccated coconut, lime zest, and salt to a mixing bowl. Mix well to combine.
Step 2
Crack the egg into the bowl. Beat the egg into the peanut butter mixture. The mixture will start to firm and form a dough.
Step 3
Divide the dough into 10 even-sized portions – roughly a tablespoon each. Roll each portion into a ball. Arrange the dough balls across the lined oven tray. Push each ball down with your palm, flattening into a cookie shape roughly 1/2 an inch thick. Ensure there is a space of at least 1.5 inches between each cookie as they will spread when baking.
Step 4
Transfer the cookies to the oven to bake for 12-15 minutes. The cookies should be lightly golden all over. Set aside to cool completely. The cookies will firm up once cooled. Store in an airtight container until ready to serve.