Grease a baking sheet lightly.
Beat together grated rind of 1 lemon, ⅔ cup granulated sugar, 6 tablespoons butter, ¾ teaspoon almond extract, ¼ teaspoon salt, and 1 ½ teaspoons baking powder in a bowl until well-combined and creamy.
Next, beat in 2 eggs and 2 to 3 tablespoons lemon juice. Add in 2 cups flour and stir with mixer at low speed until you have a smooth dough.
Place dough onto a greased baking sheet and shape it into a log. Straighten it and smooth the sides.
Bake in a preheated oven at 350 F for 25 minutes. Take out from the oven and allow to cool for 20 to 25 minutes at room temperature. Reduce the temperature of the oven to 325 F.
Fill a spray bottle with water and spritz the log lightly, covering the top and all the sides.
After 5 minutes, cut the log into ½" slices crosswise using a serrated knife. Make sure to cut evenly perpendicular to the pan otherwise the biscotti will topple over during the second bake.
Set the biscotti on the prepared baking sheet and transfer to the oven. Bake until the edges start turning golden for 30 to 35 minutes. Once done, take out from the oven and cool on a rack.
Mix together all the glaze ingredients and drizzle over the biscotti.