Heat the oven to 350 degrees F. Mix the meat, half the onions, the bread crumbs, 1/4 cup of the soup, the egg, thyme leaves, salt and pepper. Press the mixture evenly against the bottom and sides of an ungreased 9-inc pie pan. Turn the drained green beans into the meat line pan then spread the remaining soup over the beans. Bake, uncovered, for 35 minutes. Arrange the remaining onions on the top of the mixture and bake another 10 minutes. Cool for about 5 minutes, then cut into wedges and serve.