New Orleans Style Red Beans and Rice




1 pound of red beans, rinsed and sorted
2 tablespoons olive oil
1 cup chopped onion
3 celery stalks, chopped
¾ cup chopped bell pepper
3 cloves of garlic, minced
1 pound of pork sausage, sliced into ¼-inch pieces
2 bay leaves
½ teaspoon salt
¼ teaspoon black pepper
pinch of cayenne pepper
½ teaspoon dried thyme
8 cups water
½ stick butter (4 tablespoons)