Mix together a strawberry cake mix, vegetable oil, and eggs. Press into a greased 9×13 pan and bake at 350 degrees for 10-13 minutes.

Remove from the oven and top with marshmallow cream. As the marshmallow cream warms it will start to spread. Carefully spread it out over the cake mix crust pressing on the top of the marshmallow cream with a greased spatula. Set aside.

In a large bowl, melt butter in the microwave. Add mini marshmallows and stir to coat. Microwave for 45 seconds and stir until smooth. (If the marshmallows aren’t completely melted, microwave for an additional 30 seconds.) Add the fruity pebbles and gently stir until well coated. Drop by large spoonfuls over the marshmallow cream layer and carefully spread out evenly using a greased spatula. Finally, firmly press the top layer down into the marshmallow cream to really hold things together. Cover the bars and place in the fridge to cool and harden. Cut into bars and/or shapes.