Step 1

Preheat the oven to 350 degrees F.

Step 2

Line an 8x8-inch square baking pan with parchment paper.

Step 3

In a large bowl, add the cake mix, the oil, the whole egg, the egg yolk, and 1 teaspoon of the vanilla and mix with an electric hand mixer on medium speed until a thick dough forms.

Step 4

Stir the white chocolate chips into the strawberry batter.

Step 5

In another medium bowl, add the cream cheese, the sugar, the egg white, and the remaining vanilla and mix until smooth and creamy.

Step 6

Pat 1/2 of the strawberry batter into the bottom of the pan.

Step 7

Dollop the cream cheese filling over the strawberry layer.

Step 8

Drop spoonfuls of the remaining strawberry batter between the dollops of cream cheese filling until the bottom layer is completely covered.

Step 9

Bake the brownies until the center is set and a toothpick inserted into the center comes out with moist crumbs, about 28-32 minutes.

Step 10

Let the brownies cool on a baking rack for 30 minutes, then refrigerate until they are cooled completely, for at least 1 hour and up to 8 hours.

Step 11

Cut the brownies into squares and serve.