Ultra-Moist Chocolate Zucchini Loaf Cake

Why You’ll Love This Recipe

• Ultra-moist crumb where the shredded zucchini melts into the batter and virtually disappears.
• Deep, rich chocolate flavor with a cocoa aroma that fills the kitchen as it bakes.
• Comes together in one bowl for the wet and one for the dry, with simple pantry ingredients.
• Perfect for make-ahead breakfasts, afternoon coffee breaks, or an unfussy dessert.

Grocery List

• Produce: 2 medium zucchini (you need about 2 cups finely shredded)
• Dairy: Plain Greek yogurt or sour cream, 2 large eggs
• Pantry: All-purpose flour, unsweetened cocoa powder, granulated sugar, light brown sugar, neutral oil (canola/vegetable), vanilla extract, baking soda, baking powder, fine salt, espresso powder (optional), semisweet chocolate chips

Full Ingredients

Chocolate Zucchini Loaf

• 1½ cups (195 g) all-purpose flour, spooned and leveled
• ½ cup (45 g) unsweetened cocoa powder (natural or Dutch-process)
• 1 tsp baking soda
• ½ tsp baking powder
• ½ tsp fine sea salt
• 1 tsp espresso powder (optional, boosts chocolate flavor)
• ½ cup (120 ml) neutral oil (canola, vegetable, or sunflower)
• 1 cup (200 g) granulated sugar
• ½ cup (100 g) lightly packed light brown sugar
• 2 large eggs, at room temperature
• ½ cup (120 ml) plain Greek yogurt or sour cream, at room temperature
• 2 tsp pure vanilla extract
• 2 cups (260 g) finely shredded zucchini, lightly packed and lightly blotted (do not squeeze dry)
• ¾ cup (135 g) semisweet chocolate chips, plus a small handful extra for topping (optional)

Optional Finishing Touch

• Pinch of flaky sea salt for sprinkling on top, after baking

Step-by-Step Instructions

Step 1: Prep the pan, oven, and zucchini

Preheat your oven to 350°F (175°C). Lightly grease a 9×5 in (23×13 cm) loaf pan with oil or nonstick spray. Line the bottom and long sides with a strip of parchment paper, leaving an overhang for easy removal, then lightly grease the parchment as well.

Wash and dry the zucchini. Trim off the ends and finely shred the zucchini using the small holes of a box grater or a fine shredding disk on a food processor. Measure out 2 cups (260 g) of loosely packed shreds. Spread them on a clean kitchen towel or a double layer of paper towels and gently blot the surface to remove just the excess moisture. Do not wring or squeeze dry; you want plenty of moisture left for a tender, ultra-moist loaf.

Step 2: Mix the dry ingredients

In a medium bowl, whisk together the flour, cocoa powder, baking soda, baking powder, salt, and espresso powder (if using) until there are no streaks of cocoa or flour. This helps the leaveners and cocoa distribute evenly so the loaf rises well and bakes up with a uniform chocolate color.

Step 3: Whisk the wet ingredients and sugars

In a large mixing bowl, add the neutral oil, granulated sugar, and brown sugar. Whisk until the mixture looks thick and slightly creamy, about 30 seconds. Add the eggs one at a time, whisking well after each until fully incorporated and glossy.

Whisk in the Greek yogurt (or sour cream) and vanilla extract until the mixture is smooth and no streaks of yogurt remain. At this point, the batter will be pourable and slightly thick.

Step 4: Combine wet and dry for a chocolate batter

Sprinkle the dry ingredient mixture over the wet ingredients. Using a spatula or wooden spoon, gently fold the dry into the wet just until you no longer see dry flour. Scrape along the bottom and sides of the bowl to catch any pockets of flour. Avoid overmixing; a few small lumps are fine. Overmixing can make the loaf tough instead of tender.

Step 5: Fold in the zucchini and chocolate chips

Add the shredded, lightly blotted zucchini to the bowl along with ¾ cup (135 g) semisweet chocolate chips. Use your spatula to gently fold them into the batter until evenly distributed. The batter will loosen and look quite thick and glossy, with flecks of green that will mostly disappear as the loaf bakes.

Pour the batter into the prepared loaf pan and smooth the top with a spatula. If you like, scatter a small handful of extra chocolate chips over the surface for a pretty, extra-chocolatey top.

Step 6: Bake until set and fragrant

Place the pan on the middle rack of the preheated oven. Bake for 55–65 minutes, rotating the pan once halfway through. The loaf is done when the top is domed and set, a toothpick or thin skewer inserted into the center comes out with a few moist crumbs (but no wet batter), and the internal temperature is around 200–205°F (93–96°C) if checked with an instant-read thermometer.

If the top is browning too quickly before the center is done, loosely tent the loaf with a piece of foil for the last 10–15 minutes of baking.

Step 7: Cool, slice, and serve

Remove the pan from the oven and place it on a wire rack. Let the loaf cool in the pan for 15–20 minutes so it can set. If desired, sprinkle a small pinch of flaky sea salt over the top while it is still warm to enhance the chocolate flavor.

Use the parchment overhang to lift the loaf out of the pan and transfer it directly to the wire rack to cool completely. For the cleanest slices and the best texture, let the loaf cool until just slightly warm or fully cooled before cutting into 10 thick slices. Serve plain, with a swipe of butter, or alongside a cup of coffee or cold milk.

Pro Tips

• Do not over-dry the zucchini: Lightly blotting is enough. If you squeeze out too much moisture, the loaf will be drier and less tender.
• Use room-temperature eggs and dairy: This helps the batter come together smoothly and bake more evenly.
• Measure flour correctly: Spoon flour into your measuring cup and level it off, or use a scale. Too much flour is the most common cause of a dense loaf.
• Check early: Ovens vary. Start checking for doneness at 50 minutes so you do not accidentally overbake.
• Rest before slicing: Letting the loaf cool allows the crumb to set and the chocolate flavor to deepen, giving you neater slices and better texture.

Variations

• Triple chocolate zucchini loaf: Add ¼ cup (45 g) extra chocolate chips and drizzle the cooled loaf with ½ cup (85 g) melted semisweet chocolate for an even richer dessert-style loaf.
• Nutty crunch: Fold in ½ cup (55 g) chopped toasted walnuts or pecans along with the chocolate chips for extra texture and flavor.
• Warm spice twist: Add ½ tsp ground cinnamon and a pinch of nutmeg to the dry ingredients for a subtly spiced chocolate loaf that feels especially cozy in cooler weather.

Storage & Make-Ahead

Once completely cooled, wrap the loaf tightly in plastic wrap or store slices in an airtight container.

At room temperature, it will keep for 2–3 days and actually tastes even more chocolatey on day two. For longer storage, refrigerate for up to 5 days; bring slices back to room temperature or warm briefly in the microwave before serving.

To freeze, wrap the whole loaf in plastic wrap and then foil, or freeze individual slices separated by parchment. Freeze for up to 3 months. Thaw overnight in the refrigerator or for a couple of hours at room temperature. A quick 10–15 second microwave warm-up makes the crumb soft and the chocolate chips slightly melty again.

Nutrition (per serving)

Approximate values per slice (1 of 10): about 400 calories; 17 g fat; 61 g carbohydrates; 3 g fiber; 38 g sugars; 6 g protein. These numbers are estimates and will vary based on specific ingredients and portion sizes.