Mix the dough: In a large bowl, combine flour, sugar, yeast, salt, cinnamon, cardamom, and nutmeg. Add warm milk, egg, softened butter, and vanilla. Mix until a soft dough forms.
Knead: Transfer the dough to a lightly floured surface and knead for 8–10 minutes, until smooth and elastic. Avoid adding too much flour.
Add the fruit: Gently knead in the raisins, golden raisins, cranberries, candied orange peel, and almonds until evenly distributed.
First rise: Place the dough in a lightly greased bowl. Cover and let rise in a warm, draft-free place for about 1–1½ hours, or until noticeably puffy.
Shape: Place the dough on a lightly floured surface and shape it into an oval about 10–12 inches long. Make a shallow indentation slightly off-center and fold one side over to create the traditional stollen shape.
Second rise: Transfer to a parchment-lined baking sheet. Cover loosely and let rise for 30–45 minutes.
Bake: Preheat oven to 350°F (175°C). Bake for 30–40 minutes, until golden brown and baked through. If the top browns too quickly, loosely cover with foil.
Butter the loaf: Remove from the oven and immediately brush the entire loaf generously with melted butter.
Add powdered sugar: While still warm, generously sift powdered sugar over the stollen. For a thicker snowy coating, add a second layer after a few minutes.
Cool and serve: Let cool completely before slicing. For the best flavor, allow the stollen to rest for several hours or overnight before serving.