Step 1

Fruit Layer:

Step 2

In a saucepan, combine rhubarb, strawberries and juice. Cook for 10 minutes over medium heat.

Step 3

In a bowl, combine sugar and cornstarch, stir into rhubarb mixture.

Step 4

Cook and stir for 5 minutes, until thick and bubbly. Cool.

Step 5

Cake:

Step 6

Preheat oven to 375 degrees. Grease a 9x13 glass baking pan.

Step 7

Prepare cake mix as directed on box.

Step 8

Pour half of the cake batter into the baking dish.

Step 9

Scoop fruit mixture over cake batter evenly, then scoop remaining cake batter over top of the fruit.

Step 10

Bake for 40-45 minutes until cake is baked through. Set aside and cool completely.

Step 11

Frosting:

Step 12

In a large bowl, beat the butter with a hand mixer until fluffy.

Step 13

Add confectioners sugar one cup at a time, mix. Add vanilla and milk, mix until combined.

Step 14

Spread frosting evenly over cooled cake. Garnish with fresh strawberry slices if desired.