I just checked with Starbucks website --- no recipes. Starbucks is in most B&Ns and most of their goodies are made locally.

I found this one and posted it on the Desserts thread:
Don't know if you want to use a cake mix but I found this recipe:
Lemon Raspberry Crumb Bars Recipe
Ingredients
1 (18.25 ounces) yellow or white cake mix (with or without pudding)
1/2 cup (1 stick) butter or margarine, softened
1 egg
1 (14 ounces) can sweetened condensed milk
1/2 cup fresh lemon juice
1/2 pint fresh raspberries (a little over a cup)
Instructions
Preheat oven to 350 degrees F. In large bowl, combine cake mix, butter and egg. Blend on low speed until crumbly. (Do not overmix, or mixture will become sticky.)

Reserve 2 cups crumb mixture, and place remainder in greased 9 x 13-inch baking pan. Using fingers or spatula, press mixture evenly into bottom of pan. Bake for 15 minutes.

White crust is baking, prepare topping. In medium bowl, combine sweetened condensed milk with lemon juice. Stir until well-blended. (Mixture will thicken as you stir.)

Arrange raspberries evenly over surface of partially cooked crust. Pour lemon mixture over raspberries as evenly as possible. (Coverage will be thin in some places.) Sprinkle reserved crumb mixture on top.

Bake for 20 minutes more, or until lightly browned on top. Cool and cut into bars. Keep refrigerated.

From The Bar.com.