Banana Baked Donuts with Chocolate Chips

1 Preheat oven to 325F
2 Grease 2 sheets of mini bundt pans (12 pans)
3 Melt the butter -- let cool to lukewarm
4 Beat the oil, eggs, vanilla, sugar, orange zest, and buttermilk until well blended.
5 Beat in the cooled butter and banana.
6 Mix the flour, baking soda and salt and stir into the banana mixture until well blended.
7 Add chocolate chips - blend well.
8 Spoon into 12 greased mini bundt pans and bake at 325F for 20 minutes, or until a toothpick stuck into the center comes out clean.
9 Cool in pans for 10 minutes.
10 Turn out of pans and dust with confectioner's sugar or glaze with favorite glaze.