Line the loaf pan with parchment paper and Preheat the oven to 325°F.
Infuse the lemon zest in the olive oil. In a small bowl with the olive oil, add the lemon zest. Set aside to infuse while preparing other ingredients.
To make the buttermilk. Measure the milk in a liquid measuring cup, then add lemon juice and set aside to curdle.
In a medium-sized bowl, cream softened butter and sugar until creamy and fluffy.
Add the lemon-infused olive oil and eggs one at a time, beating in each addition. Until incorporated and smooth.
Add the buttermilk (milk and lemon juice) alternately with dry ingredients, in 3 to 4 additions. Until just incorporated. Do not overmix.
Pour the cake batter into the prepared loaf pan lined with parchment paper. Use a spatula to level and smooth out the top. Tap on the table/counter to knock out some air pockets.
Bake in preheated oven at 325°F for 45 minutes to 50 minutes or until the inserted toothpick/skewers or cake tester comes out clean.
Remove from the oven and cool in the pan for 10 minutes. Carefully remove from the pan, then remove the parchment paper and place it on a cooling rack with the baking sheet to catch the syrup and glaze drippings.
While the cake is still hot, brush the cake with lemon-maple syrup and let it cool completely.
Make the lemon glaze. Mix powdered sugar and lemon until smooth. Adjust to your preferred consistency. Pour and spread on top of the cake and let it drip on the sides.
Garnish with lemon zest and mint leaves, if desired.