Butter softness: It should yield easily to a light press but not look shiny or greasy; this creams smoothly and traps air for lift.
Buttermilk: Shake well before measuring. Its acidity activates the baking soda for a tender crumb.
Flour: Whisk with baking soda to remove lumps and distribute the leavener evenly.
Topping texture: Mixing sugar and cinnamon thoroughly prevents streaks and ensures an even, crackly finish.
Instructions
Prep the pan(s): Lightly grease your loaf pan(s); line with a parchment sling if you like for easy lift‑out. Preheat your oven.
Mix the dry ingredients: In a bowl, whisk together the all‑purpose flour and baking soda until evenly combined; set aside.
Cream butter and sugar: In a large mixing bowl, beat the softened butter and granulated sugar until the mixture turns noticeably lighter in color and fluffy, scraping down the bowl so everything incorporates evenly.
Add eggs and vanilla: Beat in the eggs one at a time just until incorporated, then mix in the vanilla extract until smooth and glossy.
Alternate dry and buttermilk: Add the dry mixture in portions, alternating with the buttermilk, beginning and ending with dry. Mix on low or fold gently after each addition until just combined; avoid overmixing.
Pan the batter: Scrape the batter into the prepared pan(s) and smooth the top so it bakes level.
Make the topping: In a small bowl, stir together the ⅔ cup granulated sugar and 2 teaspoons ground cinnamon until evenly blended. Sprinkle the mixture evenly over the batter, taking it all the way to the edges.
Bake: Bake until the top is golden and crackly, the loaf springs back lightly when pressed, and a tester inserted in the center comes out clean or with just a few moist crumbs (avoid any wet batter).
Cool and release: Let the bread rest in the pan briefly to set, then lift or turn out onto a rack to cool completely before slicing. This helps the crumb firm up and keeps the topping intact.
