Mix ¼ teaspoon granulated sugar, 1 Tablespoon all-purpose flour, and 2 teaspoons active dry yeast into ¾ cup warm milk (110-115°F). Let it sit in a warm place for 10-15 minutes until a bubbly froth forms.
Combine 4 cups all-purpose flour, ½ cup warm milk, 1 egg, ¼ teaspoon salt, and activated yeast starter in a mixing bowl. Use an electric mixer with a kneading hook to make a smooth, elastic dough.
Turn the dough onto a lightly floured surface and shape it into a ball. Place it in a clean bowl, cover with a tea towel or plastic wrap, and let it rise in a warm place until it doubles in size, about an hour to an hour and a half.
Once the dough has risen, roll it out into a ¼-inch thick square or rectangle. Cut it into 3-inch squares. Place 2-3 cherries in the center of each square, then pull the corners over the cherries and pinch them together.
Gently roll the dumplings into a round shape and place them seam-side down on a floured surface. Leave enough space between them, cover with a clean tea towel, and let them rest.
Meanwhile, bring water to a gentle boil in a pot and add a little of salt. The water should simmer, not boil heavily.
Place the rested dumplings seam side down in boiling water. Reduce the heat to a third, cover with a lid leaving a gap for steam, and cook for 10 minutes without flipping.
Use a slotted spoon to transfer the cooked dumplings to a bowl, and immediately prick each one twice with a fork to release any built-up steam.
Make the topping: Mix 1 cup powdered sugar and 1 teaspoon ground cinnamon in a bowl. Melt ⅓ stick unsalted butter in a saucepan.
Place two or three warm dumplings on a plate. Sprinkle one tablespoon of the cinnamon sugar topping over each dumpling. Finally, drizzle with melted butter and serve.