Preheat the oven to 325℉. Line baking sheets with parchment paper or silicone baking mats.
In a medium bowl, combine the flour, baking powder, and salt. Set aside.
2¼ cups flour, 1 teaspoon baking powder, ¼ teaspoon salt
In the bowl of a stand mixer using the paddle attachment, cream together the butter, cream cheese, sugar, and brown sugar for about 2 minutes until light and fluffy.
½ cup butter, unsalted, 4 ounces cream cheese, softened, ½ cup sugar, ¾ cup brown sugar
Add in the eggs, 1 at a time, mixing until incorporated. Add the vanilla, lemon juice, and lemon zest, and mix well.
2 large eggs, 1 teaspoon pure vanilla extract, 2 tablespoons lemon juice, 3 tablespoons lemon zest
Gently fold in the white chocolate chips.
1 cup white chocolate chips
Using a cookie scoop, form dough balls. Place them about 2 inches apart. Bake for 9 - 11 minutes, until the edges start to turn golden.
Remove from the oven and allow the cookies to cool on the cookie sheet for 5 minutes before removing them to a cooling rack to cool completely.