Preheat the oven to 350 degrees Fahrenheit. If the cookie sheet needs to be greased, do so now with cooking spray or butter.
Take the 1 cup of softened butter, 1.25 cups of white sugar and .75 cups of brown sugar and add them to the mixing bowl.Pro tip: you should be able to press the butter and leave an indentation if it is softened. This takes about an hour on the counter for a whole stick, 30 mins on the counter if cut into chunks. Or, in the microwave on defrost for 15 seconds, flip and 15 seconds (do not let it melt). Put the mixer on medium high for about 2 minutes to cream the butter and sugar together. It will be well combined, lighter and fluffier.
Add 2 eggs, 1 teaspoon of vanilla, 1 teaspoon of lemon extract and 1 tablespoon of lemon zest to the mixing bowl.
Mix on medium low speed for a minute or until well combined.
In another bowl, add 2.5 cups of flour, 1.25 teaspoons of baking soda and .25 teaspoons of salt.
Turn the mixer on low and slowly pour the dry ingredients into the mixing bowl. Mix until there are no longer flour streaks.
Take .75 cups of frozen blueberries and gently fold them into the dough.
Use a cookie scoop of tablespoon to scoop out balls of dough about 1.5 tablespoons in size.
You can roll the dough in your hands to make it tighter and more uniform.
Place balls of dough a few inches apart on the baking sheet.
Bake at 350 degrees Fahrenheit for about 14 minutes or until edges are light brown and firm.
Allow cookies to cool, centers will firm up as they cool.