Cut a circle of parchment paper to cover the bottom of each terra cotta flower pot. Then use 3 or 4 strips of parchment paper to line the sides of each pot.
Divide each thawed roll into two equal parts. Flatten each part into a small, thin circle. Using a knife, spread some softened butter on each of the circles. Take 4 of the circles and lay them out horizontally, overlapping each one over half of the top of the previous circle. Roll the circles up and then cut in half with a serrated knife. This will create 2 roses. Gently separate the petals and fold down until you have a perfect rose shape.
Place each rose roll gently down into one of the lined flower pots. Let rise for 45-60 minutes, or until doubled in size.
Whisk the egg and then brush lightly on each roll before baking for 15-20 minutes at 350 degrees F. The flower pots will be hot, so allow to cool a little before serving.