Preheat Oven at 350 degrees. Place a parchment paper on a baking sheet.
In a skillet, over medium heat, add oil and heat, add rosemary, onions cook until tender and golden, add cubed sweet potato, cook for approx. 10 minutes, add veggie medley, cook until soft and tender, add garlic, sauté until fragrant. Add salt and pepper to taste. Set aside and let cool.
In a bowl, using your hands, combine ground meat, beaten egg, veggie medley mixture, salt, and pepper, mix until all combined.
Roll out Puff Pastry, place meat mixture along one side, in a loaf form, brush edges with egg and cover until meat is covered. Ensure ends are sealed together.
Place on baking tray, brush top with egg, bake for 1 hour, until cooked and golden brown. Slice and ready to serve.