Preheat oven to 350°F (175°C)
In a large bowl, cream together the butter, white sugar, and brown sugar until fluffy
Beat in the eggs one at a time until fully incorporated
Add vanilla and lemonade concentrate, and mix well
In a separate bowl, combine flour and baking soda
Gradually add dry ingredients to the wet mixture and stir until combined
Using a cookie scoop, form even balls and place onto a baking sheet
Flatten each cookie slightly with the back of a spoon
Bake for 7–8 minutes, or until edges are just turning golden
Cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely (30–45 minutes)
Once cooled, dip each cookie quickly into the ½ cup lemonade concentrate and return to the rack
Once dipped let sit on the cooling rack for 15 minutes to absorb flavor and set
Optionally, sprinkle sugar on top immediately after dipping