2 oranges, well scrubbed and wiped dry
3 oz. bittersweet chocolate
1 c. granulated sugar
1/2 c. butter (room temperature)
2 lg. eggs
1/2 c. freshly squeezed orange juice
1/2 c. plain yogurt or buttermilk
2 c. all purpose flour
1 tsp. baking powder
1/2 tsp. baking soda

Heat oven to 375 degrees. Grease 12 regular size muffin cups. Finely grate orange peel (as little of the bitter white pith as possible). Chop chocolate into small pieces with a knife. With an electric mixer, beat sugar and butter in a bowl until pale and fluffy.

Add eggs, one at a time, beating well after each. Add orange peel, orange juice and yogurt. Mix very well. Mix flour, baking powder and baking soda. Sprinkle flour mixture, then chocolate over the batter. Fold gently, just enough to blend in the flour. Spoon into muffin cups. Bake 20 to 25 minutes or until golden brown. Turn out onto a rack. Serve warm.