1. Preheat oven to 375°F. Line muffin cups with paper liners.
2. In a large bowl, whisk the first 5 ingredients (through salt). In another bowl, grate 1 tsp orange zest and squeeze 1/4 cup juice. Whisk in the sugar, egg whites, oil, and yogurt. Stir into flour mixture just until moistened. Fold in carrots and 1 1/2 cups cranberries.
3. Divide batter among muffin cups. Top with pistachios and remaining cranberries.
4. Bake until a toothpick inserted in a muffin comes out clean (22-25 minutes). Let cool in the pan on a wire rack for 5 minutes. Unmold; cool completely on rack.