Preheat the oven to 400°F (200°C). Prepare a muffin pan by greasing it or lining it with paper liners.

In a mixing bowl, whisk together the dry ingredients: flour, baking powder, baking soda, salt, and stollen spice. Add sugar and dried fruits with candied peel.

In another bowl, mix the wet ingredients: egg, buttermilk or yogurt, and melted butter until smooth.

Fold the wet ingredients into the dry mixture until just combined.

Spoon the batter into the greased muffin cups, filling each about three-quarters full.

Bake for approximately 20 minutes, checking for doneness with a toothpick.

Cool muffins in the pan for 5 minutes, then transfer to a wire rack. Brush tops with melted butter and dust with sugar if desired.

Serve warm or at room temperature, best paired with a warm beverage.