This is not my normal kind of cake, as I almost never use a cake mix. But I first tasted something like this at a family get-together, and I asked for the recipe. This is a modification, in honor of St Patrick's Day, and I only make it on St. Patrick's Day.
1 box yellow cake mix (I like Duncan Hines)
4 large eggs
1 small box instant pistachio pudding
some freshly grated nutmeg
3/4 cup vegetable oil
3/4 cup cream sherry
Preheat oven to 350F. Grease and flour one large or two small bundt pan(s), or tube pan(s). As with most cakes it will cook in any kind of pan you like, you just have to watch the time.
Combine the cake mix and the pudding mix in a large bowl, and give it a good stir. Add all the remaining ingredients into the bowl and beat until nicely combined, but don't over beat. Pour into the pan(s) and bake about 50 minutes for the large bundt pan, until a toothpick comes out clean. Cool a bit on a rack, and then turn out of the pan before it's completely cool. If you let it cool completely it becomes rather difficult to remove.