Step 1: Preheat & Prepare the Pan
Preheat your oven to 350°F (175°C). Grease a 9×5-inch loaf pan with butter and line it with parchment paper for easy removal.
Step 2: Mix the Wet Ingredients
In a large bowl, whisk together eggs, sugar, oil (or melted butter), Greek yogurt, and vanilla extract until smooth. This mixture provides the cake’s moisture and structure.
Step 3: Combine Dry Ingredients
In a separate bowl, whisk together flour, baking soda, baking powder, and salt. Gradually fold the dry ingredients into the wet ingredients, mixing gently until just combined. Avoid overmixing to keep the cake light and fluffy.
Step 4: Make the Cinnamon Swirl
In a small bowl, stir together cinnamon, brown sugar, sugar, and cornstarch. The cornstarch helps keep the swirl mixture from sinking too much into the batter.
Step 5: Layer & Swirl the Batter
Pour half of the batter into the prepared loaf pan.
Sprinkle ¾ of the cinnamon swirl mixture over the batter.
Use a knife or skewer to swirl the cinnamon mixture into the batter.
Pour the remaining batter on top and sprinkle the remaining cinnamon sugar mixture. Swirl again gently.
Place a thin slice of butter in the center of the loaf for extra richness.
Step 6: Bake to Perfection
Bake for 55-60 minutes, or until a toothpick inserted in the center comes out clean. If the top is browning too quickly, cover loosely with foil during the last 10 minutes.
Step 7: Make the Brown Sugar Glaze
While the loaf cools, whisk together melted butter, milk, powdered sugar, brown sugar, and cinnamon until smooth. If needed, adjust the consistency by adding a little more milk.
Step 8: Drizzle & Enjoy!
Once the loaf has cooled slightly, drizzle the glaze generously over the top. Slice, serve, and enjoy your homemade cinnamon swirl loaf cake!