Preheat your oven to 350°F (175°C) and prepare a 9x13-inch baking pan by lining it with parchment paper.

In a large mixing bowl, cream together 1 cup of softened butter, ½ cup of granulated sugar, and ½ cup of brown sugar until light and fluffy.

Mix in 1 teaspoon of baking soda, ¼ teaspoon of salt, 1 ½ cups of all-purpose flour, and 1 cup of quick oats until combined.

Press half of the crumble mixture into the prepared pan and bake for 13 minutes.

Beat 8 ounces of cream cheese until smooth, then gradually add 14 ounces of sweetened condensed milk, 1 teaspoon of vanilla extract, and 1 egg yolk.

Pour the cream cheese filling evenly over the baked crust.

Sprinkle fresh blueberries over the filling and top with the remaining crumble mixture, pressing lightly.

Bake for another 20-25 minutes until the edges are golden brown and the center is set.

Allow the bars to cool completely in the pan for about an hour before transferring to the refrigerator to chill for at least another hour.