Begin by boiling enough water to fully submerge the dumplings in the baking dish, plus an additional ½ cup. Allow the biscuit dough to rest at room temperature while preparing the apples for easier rolling.

Peel and finely chop the apples, then combine them in a bowl with the ground cinnamon, stirring thoroughly to coat the pieces evenly.

Roll out each biscuit into a flat circle. Place a generous tablespoon of the cinnamon-spiced apple mixture in the center of each. Encase the filling by pulling the dough around the apples and pinching the seams closed.

Arrange the dumplings seam-side down in a 13x9-inch baking dish. Continue this process until all 20 dumplings are filled and positioned in the pan.

Slice the butter into small pats and distribute evenly over the top of the dumplings. If any apple mixture remains, scatter it over the dumplings as well.

Evenly sprinkle the granulated sugar across the surface. Carefully pour the boiled water over the dumplings, ensuring they are fully submerged, followed by an extra ½ cup to promote syrup formation during baking.

Place the baking dish in a preheated 350°F oven and bake for 1 hour, or until the dumplings are golden and the syrup is bubbling.