Prepare the Dough:

1. In a small saucepan, heat the plant-based milk and dairy-free butter until warm (about 110°F). Remove from heat and sprinkle the yeast over the mixture. Let it sit for 5-10 minutes until foamy.
2. In a large bowl, whisk together the flour, granulated sugar, salt, cinnamon, and allspice.
3. Add the yeast mixture to the dry ingredients, mixing until a soft dough forms.
4. Turn the dough out onto a floured surface and knead for about 5-7 minutes, until smooth and elastic.
5. Place the dough in a greased bowl, cover with a damp cloth, and let it rise in a warm place for about 1 hour, or until doubled in size.

Prepare the Filling:

1. Scoop the Biscoff spread into small spoonfuls and place them on a lined baking sheet. Freeze for about 30 minutes until firm.

Assemble the Buns:

1. Punch down the risen dough and divide it into 6 equal pieces.
2. Flatten each piece of dough and place a frozen scoop of Biscoff spread in the center.
3. Carefully seal the dough around the Biscoff, forming a ball.
4. Place the buns on a greased baking sheet, cover with a damp cloth, and let them rise for another 30 minutes.

Add the Cross:

1. In a small bowl, mix the flour and water to make a thick paste.
2. Transfer the paste to a piping bag or a plastic sandwich bag with a tiny corner snipped off.
3. Pipe a cross over the top of each bun.

Bake the Buns:

1. Preheat your oven to 350°F (175°C).
2. Bake the buns for 20-25 minutes, or until golden brown.
3. Allow the buns to cool slightly before serving.

Serve:

1. Serve the buns warm for the ultimate melty Biscoff experience.