The Ultimate Tender Slow Cooker Steak Pie

"This comforting slow-cooked stew features tender beef chunks simmered in a thick, peppery gravy with fresh celery and carrots and a flaky puff pastry top. There is nothing better than to come home to a piping hot comforting dinner that requires very little effort. And this easy slow-cooker beef pie is one of the best. Slow cooker recipes are always an easy dinner-time win at this time of year. Not only do slow cookers create the most amazing flavourful meals, but they are also very cheap to run and require very little effort. "