In a large bowl, mix together the flour, sugar, salt, cinnamon, nutmeg, and allspice.
In a small saucepan, heat the plant-based milk and vegan butter until the butter is melted. Let the mixture cool to room temperature.
Once the milk mixture has cooled, add it to the flour mixture along with the yeast and dried cranberries or raisins. Mix until the dough comes together.
Knead the dough on a floured surface for 5-10 minutes, or until it becomes smooth and elastic.
Place the dough in a greased bowl and cover it with a damp cloth. Let it rise in a warm place for 1-2 hours, or until it has doubled in size.
Once the dough has risen, punch it down and divide it into 12 equal pieces. Shape each piece into a ball and place them on a greased baking sheet. Cover with a damp cloth and let them rise for another 30 minutes.
Preheat the oven to 375°F (190°C). Mix together the powdered sugar, vanilla extract, and unsweetened plant-based milk to make the glaze.
Once the buns have risen, use a sharp knife to make a cross on top of each bun. Brush them with the glaze.
Bake the buns for 20-25 minutes, or until they are golden brown. Let them cool on a wire rack.