Heat coconut oil in a large saucepan on medium heat. Add the onion, carrots and celery and cook for five minutes. Next add the beef mince and cook until browned. Then, mix through the thyme, tapioca flour and season with salt and pepper. Finally, add the crushed tomatoes, tomato paste, Worcestershire sauce and beef stock and simmer for 30 minutes, stirring occasionally.
To make the topping; add the sweet potato to a large saucepan with water and bring to the boil. Cook for 10 minutes or until the potatoes are tender. Remove from the heat and drain the water. Add the butter and almond milk and mash. (My preference is with a potato ricer as there is never any lumps). Season with salt.
While you are cooking the potatoes, pre-heat the oven to 200 degrees celcius.
Place the cooked beef mixture in the bottom of one large baking dish or divide among 6 individual pie dishes (like in the pictures above). Then, top with the sweet potato mash and place in the oven for 15-20 minutes, or until the potato has just started to brown and the edges are bubbling.
Serve with a side salad.