Preheat the oven to a moderate 350°F / 180°C
Grease and line a 9 x 5 inch loaf pan with baking paper, extending over the sides. NOTE 2
Toss the cranberries with 1 tablespoon flour and set aside. NOTE 3
Cream the butter and sugar until creamy, about 2 minutes
Add the eggs and lemon zest and beat until combined.
In a separate bowl, sift together the flour, baking powder, and salt. Add half of the sifted flour mixture to the creamed butter , sugar and egg mixture and mix on low speed just until combined.
Pour in half of the milk and mix on low speed just until combined.
Add the rest of the flour, mixing just until combined, and then the remaining milk.
Stir in the cranberries and mix a few seconds longer.
Pour the batter into the pan and bake 45-60 minutes, until a skewer inserted comes out clean
Cool the cake for 15 minutes in the pan and then remove it from the pan, lifting it out with the baking paper. Remove the baking paper before pouring on the glaze.