Preheat the oven to 325°F. Line an 8×8 baking pan with foil or parchment paper, set aside.
Mix the crushed oreos with the butter and press into the pan.
18 Golden Oreos, 3 tablespoons unsalted butter
In a large bowl with a hand mixer, or in the body of a stand mixer with the paddle attachment, add the cream cheese to the bowl and mix on medium until there are no lumps.
8 ounces cream cheese
Add the sour cream, sugar, vanilla, egg, flour, lemon juice, and lemon zest. Mix until combined on medium speed, scrape down the sides of the bowl as needed.
1/3 cup sour cream, 1/3 cup granulated sugar, 1/2 teaspoon vanilla extract, 1 large egg, 2 tablespoons all-purpose flour, 1 tablespoon lemon juice, 1 lemon
Add 3/4 of the blueberries and fold them in, pour into the 8×8 pan on top of the crust. Top with the remaining blueberries.
1 cup blueberries
Bake for 36 minutes, until the center is very slightly jiggly and the edges start to brown. Let the pan cool completely on the counter, cover, and chill in the fridge for 4 hours or up to overnight to set.
Notes
Room Temperature Ingredients: Make sure your cream cheese and sour cream are at room temperature for smooth mixing.
Fine Crumbs: For a perfect crust, make sure your Oreos are crushed into fine crumbs. Using a food processor is the best way.
Fresh is Best: Use fresh lemon juice in this dessert bar for the best lemon flavor.
Mix on Medium: Mixing on medium speed ensures a creamy texture.
Gentle Folding: Gently fold in the plump blueberries to keep their shape.
Patience Pays: Let the bars chill well before you cut into them; it makes a huge difference in texture.