Cinnamon Donut Loaf Cake

There is something about the smell of cinnamon hitting a warm oven that makes the whole kitchen feel like a Sunday morning, even on a random Tuesday. I threw this loaf together once when a friend showed up unannounced and I had nothing to offer but bad coffee and apologies. Within an hour the house smelled like a bakery and we were standing at the counter tearing off pieces before it even cooled. That is the magic of a cinnamon donut loaf: it turns an ordinary afternoon into something worth remembering.

I have made this loaf for book club, for a neighbor who just had a baby, and once at midnight because I could not stop thinking about it. Every single time someone asks for the recipe before they finish their first slice. The loaf disappears fast, so I have learned to make two.

Ingredients

• All purpose flour (2 cups, 250 g): Spoon and level it rather than scooping straight from the bag to avoid a dense loaf.
• Granulated sugar (3/4 cup, 150 g): Just enough sweetness without making it cloying, letting the cinnamon shine.
• Baking powder (2 tsp): Gives the loaf its signature fluffy lift.
• Baking soda (1/2 tsp): Works alongside the baking powder for an even, reliable rise.
• Salt (1/2 tsp): Do not skip this, it sharpens every flavor in the crumb.
• Ground cinnamon (1 tsp plus 1 tsp for topping): Use fresh cinnamon if you can, the aroma difference is real.
• Large eggs (2): Room temperature eggs blend more smoothly into the batter.
• Whole milk (3/4 cup, 180 ml): Whole milk gives the richest crumb, though you can sub with what you have.
• Unsalted butter, melted and cooled (1/2 cup, 113 g): Let it cool so you do not scramble the eggs or melt the sugar oddly.
• Pure vanilla extract (2 tsp): A generous pour adds warmth and depth to every bite.
• Melted butter for topping (1/4 cup, 56 g): This is what makes the cinnamon sugar stick and creates that irresistible crust.
• Sugar for topping (1/3 cup, 65 g): A crunchy, sweet layer that transforms a simple loaf into something special.

Instructions

Set the stage:

Preheat your oven to 350 degrees F and grease a 9 by 5 inch loaf pan, then line it with parchment paper so the loaf releases cleanly every time.

Build the dry mix:

In a large bowl, whisk together the flour, sugar, baking powder, baking soda, salt, and cinnamon until evenly distributed and there are no pockets of leavening.

Whisk the wet team:

In a separate bowl, combine the eggs, milk, cooled melted butter, and vanilla extract, whisking until smooth and slightly frothy on top.

Bring it together:

Pour the wet ingredients into the dry and stir gently with a spatula just until you no longer see dry flour streaks, the batter will be thick and that is exactly right.

Into the pan:

Transfer the batter to your prepared loaf pan and smooth the top with the back of a spoon so it bakes evenly.

Bake and watch:

Bake for 40 to 45 minutes, checking at the 40 minute mark with a toothpick inserted into the center, it should come out clean with just a few moist crumbs.

Cool briefly:

Let the loaf sit in the pan for 10 minutes to set its structure, then turn it out onto a wire rack.

Brush with butter:

While the loaf is still warm, brush the top and sides generously with melted butter so every surface gets that glossy coating.

Apply the cinnamon sugar:

Mix the sugar and cinnamon in a small bowl, then sprinkle and gently pat it all over the buttered surfaces until completely and evenly coated.

Let it rest:

Allow the loaf to cool completely before slicing so the crumb sets and the topping adheres beautifully.

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The best thing I ever did with this loaf was pack it in a paper bag and bring it on a road trip. We ate it in the car with bad gas station coffee and it still tasted like absolute heaven.

Variations Worth Trying

Stir half a cup of mini chocolate chips into the batter for a mocha donut vibe that pairs beautifully with the cinnamon. You can also swap half the vanilla extract for almond extract, which adds a subtle nuttiness that catches people off guard in the best way.

What to Serve It With

A thick slice of this loaf next to a steaming mug of coffee or chai is honestly all you need on a quiet morning. It also holds up beautifully as a dessert with a scoop of vanilla ice cream on the side if you want to dress it up.

Storage and Make Ahead

Wrap leftover slices tightly in plastic wrap and keep them at room temperature for up to three days. You can also freeze the whole loaf or individual slices for up to a month.

• Reheat a frozen slice in the oven at 300 degrees F for about 10 minutes and it tastes freshly baked.
• If the topping softens in storage, pop the slice under the broiler for 30 seconds to crisp it back up.
• Always let the loaf cool completely before wrapping or condensation will make the crust soggy.

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This loaf is proof that you do not need a fryer or fancy equipment to capture the soul of a cinnamon donut. Just a mixing bowl, a little patience, and the willingness to share.

Recipe Q&A

→ Can I use a different size loaf pan?

A 9x5-inch loaf pan is ideal for this batter. If using an 8x4-inch pan, the loaf will be taller and may need an additional 5–10 minutes of baking time. Check doneness with a toothpick inserted into the center.

→ How should I store the cinnamon donut loaf?

Store the cooled loaf wrapped tightly in plastic wrap or in an airtight container at room temperature for up to 3 days. For longer storage, freeze individual slices wrapped in foil for up to 2 months.

→ Can I make this loaf dairy-free?

Yes, substitute the whole milk with an equal amount of oat milk or almond milk, and replace the unsalted butter with a plant-based butter alternative. The texture will be slightly different but still delicious.

→ Why is my loaf dense instead of fluffy?

Overmixing the batter is the most common cause. Stir the wet and dry ingredients together only until just combined—some small lumps are perfectly fine. Also ensure your baking powder and baking soda are fresh and active.

→ Can I add mix-ins to the batter?

Absolutely. Fold in up to 1/2 cup of mini chocolate chips, chopped pecans, or raisins after combining the wet and dry ingredients. Gently stir them in to avoid overworking the batter.

→ When should I apply the cinnamon-sugar topping?

Brush the loaf with melted butter and apply the cinnamon-sugar coating while the loaf is still warm but out of the pan for about 10 minutes. The warmth helps the butter absorb and the sugar adhere evenly to the crust.