Prep Your Zucchini: Grate your zucchini, then sprinkle it lightly with 1/4 teaspoon of salt. Place it in a sieve over a bowl and let it drain for about an hour. After draining, give it a good squeeze to remove as much moisture as possible – this step is key for perfect bread!
Make the Creamy Swirl: While the zucchini is draining, preheat your oven to 350°F (175°C) and lightly grease a metal loaf pan. In a medium bowl, beat the softened cream cheese until it's wonderfully smooth. Stir in the powdered sweetener and 1/2 teaspoon of the vanilla extract until everything is well combined and creamy. Set this aside.
Whip Up the Chocolate Batter: In a separate large bowl, whisk together the almond flour, granulated sweetener, cocoa powder, protein powder, baking powder, and the remaining 1/4 teaspoon of salt. Once dry ingredients are mixed, add the drained zucchini, eggs, melted butter, and the remaining 1 teaspoon of vanilla extract. Stir gently until just combined. The batter should be thick enough to scoop, but if it feels too dense, add a tablespoon of water at a time until it's scoopable.
Assemble and Bake Beautifully: Spoon half of the chocolate batter into your prepared loaf pan, spreading it evenly. Dollop half of the cream cheese mixture over the batter. Grab a knife and gently swirl it through to create a lovely marble effect. Repeat this layering with the remaining chocolate batter and cream cheese mixture. Bake for 45 to 60 minutes, or until the top of the bread feels firm to the touch. (Don't worry if the cream cheese swirl still feels a bit soft – that's perfect!)
Cool and Enjoy: Let the bread cool in the pan for about an hour. Then, carefully run a sharp knife around the edges, flip it out onto a plate, and let it cool completely on a wire rack. This ensures it sets perfectly for slicing.