Preheat the oven to 350 degrees. Grease a large bread pan and set aside.

Whisk together flour, salt, baking powder together in a bowl. In a separate bowl mix eggs, sugar, zest of the whole lemon, rosemary, and olive oil until combined. Add the dry ingredients and the milk, and stir until just combined. Pour batter into the bread pan.

Thinly slice the lemon, remove seeds, and place on top of the batter. Sprinkle the last tablespoon of sugar evenly on top of the lemons.

Place loaf pan in the oven and bake for 70 minutes or until a toothpick comes out clean in the center. After cooling, dust lightly with powdered sugar. Cut and serve with a sharp serrated knife.