Preheat oven to 350° and ensure rack is set in the middle.
Bring a large pot of salted water to a simmer. Add chicken breasts, thyme and bay leaf. Simmer gently for 5 minutes. Turn heat off and cover for additional 5 minutes.
Rinse and trim woody ends from asparagus. Line up evenly from the top and cut into 5 cm (2 inch) chunks. Add to chicken poaching pot after the second 5 minutes. Cover and allow to heat for 5 minutes. Remove chicken to cutting board and allow to cool slightly. Drain and rinse asparagus with cool water. Discard thyme and bay leaf.
In a large bowl combine soup, mayonnaise, lemon juice, curry powder, chives and salt and pepper. Add asparagus chunks. Cut chicken into small chunks and add to sauce.
Remove caps from puff pastry shells with a sharp knife or spoon. Lay aside to top pastries after baking. Arrange shells on a large baking sheet. Fill generously with chicken and asparagus mixture. Bake on the middle rack for about 30 minutes until filling is hot.
Sprinkle with reserved chives and place cap on top for serving.