Position an oven rack in the center and preheat the oven to 325°F (160°C). Prepare a 10-cup Bundt pan by coating it thoroughly with non-stick cooking spray and dusting lightly with flour.
In a large mixing bowl, beat the softened butter and granulated sugar with an electric mixer on medium speed until the mixture is light and fluffy, about 3-5 minutes.
Incorporate the eggs one at a time, ensuring each is fully blended before adding the next. Stir in the vanilla extract and lemon zest until just combined.
In a separate medium bowl, whisk together the all-purpose flour, baking powder, and salt.
Gradually add the dry ingredients to the wet mixture, alternating with the whole milk. Begin and end with the flour mixture, mixing on low speed until just combined after each addition; do not overmix.
Pour the prepared batter evenly into the greased Bundt pan.
Bake for 70 to 75 minutes, or until a wooden skewer inserted into the deepest part of the cake emerges clean. If the top browns too quickly, loosely tent with aluminum foil.
Allow the cake to cool in the pan on a wire rack for 15 minutes before carefully inverting it onto the rack to cool completely. Slice and serve at room temperature.