Combine flour, sugar, and yeast in a bowl. Warm milk to 110°F and add to dry ingredients. Mix in beaten egg and melted butter to form a sticky dough. Knead for 5-7 minutes until smooth.

Mix brown sugar, cinnamon, and softened butter in a bowl for the filling. Set aside.

Roll out the dough into a 12x18 inch rectangle. Spread the filling evenly over the surface.

Roll the dough tightly from the long edge and slice into 12 pieces. Place in a greased baking dish.

Cover the dish and let the rolls rise in a warm place for about 30 minutes.

Preheat oven to 350°F. Bake rolls for 25-30 minutes until golden brown.

Mix powdered sugar, milk, and vanilla extract until smooth for the icing.

Drizzle icing over warm rolls and top with gummy worms.