Preheat oven to 325F and line a baking sheet with parchment paper.
In a large bowl, whisk together almond flour, granulated Swerve, baking powder and xanthan gum. Stir in orange zest and cardamom.
Stir together melted butter, egg, and vanilla extract until dough comes together.
Turn dough out onto baking sheet and form into low, flat log, 10 x 4 inches. Bake 25 minutes, or until lightly browned and firm to the touch. Remove from oven and let cool 30 minutes. Reduce oven temperature to 250F.
With a sharp knife, gently cut into 15 even slices. Place slices back onto baking sheet cut-side down and bake for 15 minutes, then flip each slice and continue to bake for another 15 minutes. Turn off oven and let sit inside until cool.
For the glaze, whisk together the powdered Swerve with the orange juice. Drizzle over cooled biscotti and let set 30 minutes.
Serves 14. Each serving has 3.91 g of carbs and 1.79 g of fiber. Total NET CARBS = 2.12 g.Food energy: 123kcal Saturated fatty acids: 2.65g Total fat: 11.06g Calories from fat: 99 Cholesterol: 8mg Carbohydrate: 3.91g Total dietary fiber: 1.79g Protein: 3.75g