Preheat oven to 350 and grease an 8x11 or 9x13 baking dish. Tear the bread into roughly 1” chunks and place in a very large bowl. Melt the butter in a large skillet over medium heat and add the sausage, leeks, celery, garlic, salt and pepper. Saute for 5 minutes, stirring occasionally. Pour the leek mixture over the bread and sprinkle with the herbs. Stir to combine. Pour the broth over the mixture and stir again. Add the eggs and toss again. The bread mixture should feel pretty wet, if it feels too dry, add more broth. Transfer the mixture to your greased baking dish. Drizzle with butter and bake, covered for 30 minutes. If the stuffing is still pretty wet, uncover and cook for 5-10 minutes more