Can anyone give me some tips to make my cupcakes come out less spongy. The batter is thick but when it's done baking they have a spongy texture that I don't like. I am looking for a more dense, homemade texture and taste. I made some hawaiian cupcakes with pineapple, cherries and coconut cream pudding and they came out perfect but for some reason this base which I use for my chocolate chip cookie dough cupcakes came out very light and spongy. Here is what I do:

1 box DH yellow cake mix
1 pkg. vanilla pudding
4 eggs
1/3 cup melted butter
1 1/3 cups milk
1 tsp butter flavoring

Thanks for your help!!