Preheat your oven to 350°F (175°C). Generously grease and flour a 10-inch Bundt pan, tapping out any extra flour—this helps the cake release cleanly.

In a large bowl, cream butter and sugar on medium speed for 3–4 minutes until pale and fluffy. You’ll see soft peaks form—that’s your cue.

Beat in eggs one at a time, scraping down the sides after each addition. Add vanilla and lemon zest, stirring until fragrant.

Whisk together flour, baking powder, baking soda, and salt in a separate bowl.

Alternate adding dry mixture and buttermilk to the creamed butter: begin and end with flour, mixing on low until just combined each time (three additions). Over-mixing will toughen the cake.

Pour batter into the prepared pan, smoothing the top. Give the pan a gentle tap on the counter to pop any air bubbles. Bake for 45–55 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.

While the cake bakes, whisk together 1 cup (120g) powdered sugar and 3–4 tablespoons fresh lemon juice to make a smooth glaze. Adjust with more juice or sugar for desired consistency.

Cool cake in pan for 10 minutes, then invert onto a wire rack set over a baking sheet. Drizzle the warm cake with glaze, letting it soak into every groove. Allow at least 30 minutes for the cake to set before slicing.