Spray a 9-inch springform pan with cooking spray. Line the bottom of the pan with parchment paper and lightly spray the paper. Preheat oven to 350 degrees.
In a food processor, combine 3¼ cups almond flour, salt, and baking soda and pulse a few times to combine. Add the eggs, apple sauce, honey, and vanilla and process until smooth.
In a large mixing bowl, combine the blueberries with 1 tablespoon almond flour, tossing to coat. Pour the batter into the bowl and fold gently to stir the blueberries into the batter. Pour the mixture into the prepared pan.
In a small bowl, combine the coconut sugar, cinnamon, and sliced almonds. Sprinkle on top of the cake and bake for 60 – 70 minutes or until a toothpick inserted into the center comes out clean. It is a good idea to start checking the cake after 45 minutes. If it is getting too dark on top, place a piece of foil loosely over the top while it finishes baking. Let the cake cool in the pan for 15 minutes.