Line a baking dish with parchment paper, or grease it.
On a floured surface, spread the dough in 1 rectangle.
Spread the butter/cinnamon over the entire surface.
Spread the apples.
Starting from the longest side, roll the dough.
Cut 12 pieces of identical size (this is where the filling can escape).
Place the snails in the baking dish, face upwards, leaving a space between them (as they will rise).
Cover with a clean cloth and let them rest for 1 to 1.5 hours. The buns will rise.