I saw this idea in my local paper last Wednesday. I thought it was adorable, but didn't have ingredients, so I stored it in the back of my sometimes-scattered brain. The kids were delighted, my dearly beloved said it looked like a restaurant dessert, and a good time was had by all - except me, that is - I ate my berries straight, with nonfat milk and no sugar - booorrrring, I know....
Anyway, you can use 1-1/2 cups of yellow cake mix with one egg, 2 tbsp. vegetable oil and 5/8 cup water, beaten together for 2 minutes, to make about 8 cup cakes, or you can try this old recipe, adapted from my 1950s era McCalls cookbook:
YELLOW CAKE (Size: Small)
1-1/2 cups flour
1-1/4 tsp baking soda
1/2 tsp salt
6 tbsp. butter
3/4 cup sugar
1/2 tsp vanilla
1/2 cup milk
Sift together the first three ingredients and set aside. Beat together the butter, sugar, egg & vanilla until smooth. Add the flour mixture and milk alternately. Beat until smooth.
Spray the entire inside of coffee or tea cups with nonstick goop, and place them on a large baking tray. Spoon the batter into the cups, filling them only 1/3 to half full. Place the tray in a cold oven, so as to reduce the possibility of breaking your cups, turn the oven on to 350, and bake 20 to 25 minutes (maybe more, depending upon the size of your cups). They will take about 5 minutes longer than you think, because you're starting with a cold oven. When they test done with a toothpick, put the entire tray aside for a few hours to cool.
To serve, place each cup on a saucer. Whip about 1-1/2 cups heavy cream with 1 tsp vanilla extract and 1/2 cup sugar until fluffy but not hard. Spoon a liberal amount of whipped cream onto each cup cake, then top with blueberries and strawberries. Just before serving, for the fireworks, sprinkle pop rocks on top of each cup cake! It's a riot to listen to your dessert popping away - when you have 5 of them making noise right beside you, it's pretty loud. All of the kids thought this was a really fun dessert, and they thoroughly enjoyed every bite of it!