Heat Things Up: Preheat that oven of yours to a snug 350°F (177°C). Lightly gloss over two 9x5-inch loaf pans with a bit of butter or cooking spray. Set 'em aside for now.

Whip It Good: In a roomy mixing bowl, wield your handheld mixer to cream the butter, sugar, eggs, and vanilla into a smooth concoction. Once harmonized, fold in the buttermilk, flour, and baking soda using a rubber spatula. Mix just until the flour mafia is inducted into the creamy family—no lumps allowed.

Cinnamon-Sugar Alchemy: In a petite bowl, cast in your cinnamon and sugar, swirling them together until well-mingled.

The Layering Game: Take half of your prepared batter and equally divvy it up between the two pans you set aside. Unveil your cinnamon-sugar mix, generously sprinkling about 75% of it over the batter in each pan.

Cover and Sprinkle: Blanket this sugary layer with the remaining batter. Now, don't forget that last 25% of your cinnamon-sugar mix; let it snow right on top of your loaves.

Swirl, Baby, Swirl: For some culinary flair, grab a butter knife and artfully carve a few swirls into the batter of each pan. This isn't just for show; it marries the flavors.

Bake Your Heart Out: Send your loaves into the preheated oven. Bake for about 45 minutes. The ultimate test? A toothpick coming out clean when poked near the middle.

The Waiting Game: Once out of the oven, grant them a 20-minute cool-off in their pans. After, transition them to wire racks until they’re cool as a cucumber.