Preheat your oven to 350°F and lightly grease a 9x5-inch loaf pan or line it with parchment paper for easy removal.
In a large mixing bowl, whisk together the brown sugar, Greek yogurt, apple butter, eggs, milk , and vanilla until the mixture is smooth and well combined.
In the same bowl (to keep it simple!), add the flour, baking soda, baking powder, cinnamon, nutmeg, and salt..
Stir gently until the dry ingredients are just incorporated. Don’t overmix or the loaf can turn dense!
Pour the batter into your prepared pan and smooth the top with a spatula.
Bake for 45–50 minutes, or until a toothpick inserted in the center comes out clean or with just a few crumbs.
Cool the loaf in the pan for 10 minutes, then transfer it to a wire rack to cool completely before slicing.
Notes
For best results, use high-quality apple butter for richer flavor and even texture.
If the bread starts to brown too quickly, loosely tent the top with foil during the last 10–15 minutes of baking.
Store leftovers in an airtight container for up to 3 days at room temperature or freeze up to 3 months.