Preheat oven to 350°F and spray a 9x5-inch loaf pan with nonstick baking spray.
Toss the cranberries with 1 tablespoon of flour; set aside.
1 cup fresh cranberries, 1⅔ cups all-purpose flour
In a medium bowl, whisk the rest of the flour, baking powder, and salt together.
1½ teaspoons baking powder, ½ teaspoon kosher salt
In the bowl of a stand mixer fitted with the paddle attachment, cream the butter and sugar together on medium-high speed until fluffy and creamy, about 1-2 minutes.
½ cup unsalted butter, 1 cup granulated sugar
Add the eggs and beat an additional 1 minute.
2 large eggs
Add half of the flour mixture; mix on low speed just until incorporated.
Add ¼ cup (half) of the milk and mix on low for 15 seconds.
½ cup milk
Add the remaining flour mixture and mix just until no flour is visible.
Add remaining ¼ cup milk and mix until combined.
Fold in the lemon zest and cranberries.
1 tablespoon grated lemon zest
Pour the batter into the prepared loaf pan and bake, at 350°F, for 50-60 minutes or until a toothpick inserted in the middle comes out clean.
Transfer the bread (in the pan) to a cooling rack and cool 15 minutes. After 15 minutes, remove the loaf from the pan, and set it upright.