Start by preparing the dough. Heat the milk on the stovetop or in the microwave to approximately 120°F.
Pour the warm milk into a large mixing bowl, add the sugar, and sprinkle the dry active yeast over the top. Let the yeast and milk stand for about 5 minutes, until it becomes foamy (skip this waiting step if using instant yeast).
Next, add in the egg, melted butter (cooled), salt, and vanilla extract. Whisk for a few minutes until the mixture is smooth.
Gradually begin adding in the flour. You’ll need about 4 to 4 ½ cups of flour for the dough. Whisk the flour in at first, then switch to a spatula once the batter thickens.
Once a dough ball starts to form, turn it out onto a well-floured work surface and begin to knead, adding more flour as needed. The dough should be very soft but not sticky! Knead the dough for 5 to 6 minutes, until it’s smooth and elastic.
Place the dough back into the mixing bowl and cover the bowl with a clean kitchen towel. If using conventional yeast, allow the dough to proof in a warm corner of the kitchen for 1 to 1 ½ hours, until the dough is doubled in size. If using fast-acting yeast, allow the dough to rest for 15 to 20 minutes while preparing the filling.
Preparing the Filling:
Use a cherry pitter to remove the cherry pits or split each cherry in half with a small knife. For larger cherries, cut them into quarters; for smaller cherries, cut them in half.
Place the cherries into a large mixing bowl and add the cornstarch, sugar, vanilla, and salt. Use a spatula to mix everything together until the cherries are well coated.
How to Make Cherry Buns:
Line two large baking sheets with parchment paper or silicone mats.
Transfer the dough onto a lightly floured work surface and use a knife or bench scrapper to divide the dough into 16 equal pieces – divide it in half, then in half again, and so on. Keep the pieces covered with a kitchen towel to prevent drying.
For each bun – gently roll a piece of dough into a 6-inch circle. Place ½ cup of the cherry filling into the center.
Gently bring the dough up and around the filling, pinching it at the top. Try not to get any cherry juice on the edges. Pinch all the seams together, bringing them together in the center.
Place the shaped buns seam side down onto the prepared baking sheets. Space the buns a few inches apart.
Beat 1 egg with 1 tablespoon of water in a small bowl, then use a pastry brush to apply the egg wash over each bun.
Proofing & Baking:
Once all the buns are shaped, begin preheating the oven to 350°F.
Proof the buns for 30 to 50 minutes, until the dough is fluffy. Keep the buns next to the preheating oven – the heat will help proof them faster.
Bake the buns at 350°F for 22 to 24 minutes, until they are a rich, golden-brown color on top. The buns will seep cherry juice as they bake; this is normal. I recommend baking one pan at a time for even baking.
Remove the buns from the oven, let them rest on the baking sheet for 10 minutes, then gently lift them off the pans onto a wire rack to cool.
Serving & Storing:
These baked cherry buns will be extremely hot when they come out of the oven, especially the filling. Allow them to cool for at least 20 to 30 minutes prior to enjoying.
Keep the buns stored at room temperature in an airtight container for up to 2 days. For longer storage, they can be refrigerated or frozen.