Preheat your oven to 325°F. Generously grease a 9 to 12-cup bundt pan so your cake slips out easily.
In a large bowl, whisk together the almond flour, sweetener, cocoa powder, coconut flour, protein powder, baking powder, and salt.
Stir in the eggs, melted butter, and vanilla extract. Fold in the grated zucchini until a thick, spreadable batter forms. If it feels too stiff to spread, stir in a splash of cold coffee or water.
Spread the batter evenly into your prepared bundt pan. Bake for 40 to 50 minutes until the top feels firm. Let it cool in the pan for 30 minutes, then carefully flip it onto a serving plate to cool completely.
Gently heat the heavy cream in a small saucepan until it just begins to simmer. Remove from heat, stir in the chopped chocolate until melted, then whisk in the powdered sweetener and vanilla until completely smooth.
Let the chocolate glaze cool and thicken for a few minutes, then drizzle it beautifully over the top of your cake.