1. Place sugar and cinnamon in a small bowl and stir to combine. Set aside.

2. On a lightly floured work surface roll out dough 1/8-inch thick rectangle. Brush surface all over with egg. Sprinkle with cinnamon sugar mixture in an even layer to cover. Any remaining cinnamon sugar may be reserved for another use. Fold dough in half lengthwise to enclose cinnamon sugar. Trim edges, discarding scraps. Cut lengthwise strips 3/4-inch-wide. Twist each strip and roll into a spiral. Let rest in a warm place until dough is doubled in bulk, about 45 minutes.

3. Preheat the oven to 375 degrees. Fill the center of each spiral with a small dollop of apricot jam. Brush dough with the remaining beaten egg. Bake, rotating sheets halfway through, until pastries are evenly browned, 20 to 25 minutes. Transfer to a wire rack to cool. Serve at room temperature. Snails are best eaten the same day they are made.