Preheat the oven to 350 degrees F. Grease and line a parchment paper over a square pan and set aside.
To prepare the streusel; combine almond flour , sweetener, melted butter, cinnamon and coffee powder in a large bowl. Mix it evenly to form a crumble-like texture. Keep it aside.
To prepare the cake batter; combine the dry ingredients in a medium bowl; almond flour, sweetener, baking powder and salt. Mix well and aside.pr
In a separate large bowl beat the eggs along with the butter, almond milk and vanilla extract to form a homogeneous mixture.
Add the dry ingredients mixture in batches to the liquid mixture until it forms a smooth batter without any lumps.
Transfer half of the batter into the prepared pan, spread half of the prepared streusel evenly over the batter. Add the remaining cake batter over and top it with the remaining streusel.
Bake the cake for 35-40 minutes until the toothpick inserted in the center comes out clean. Once done, allow the cake to cool down for at least 1 hour .
Meanwhile prepare the glaze by combining the powdered sweetener and almond milk in a bowl. Mix it to form a syrupy consistency.
Drizzle the glaze over the cake and cut it into equal squares and serve.