Make the dough for the empanadas: mix the butter, milk, vinegar and salt together until well combined. Stir in the flour until you have a soft dough - it should not be stiff like normal bread dough. Place on a lightly floured surface and knead for 5 – 8 minutes. Shape into a ball and cover with plastic. Set aside in the fridge to chill.
Start the filling by heating the olive oil in a large heavy-based pot. Sauté the onion until translucent – about 5 minutes. Add the garlic, chilli, cumin seeds and tomato paste and cook for 5 – 8 minutes, or until fragrant.
Place the sweet potato and vegetable stock in the pan and gently simmer until the liquid has reduced by ¾ and the sweet potato is soft, adding a little more stock should it be necessary.
Add the KOO Kidney Beans and leave to cook until the mixture is dry. Using the back of a spoon, mash the vegetables slightly. Stir through the KOO Mixed Vegetables and the rest of the ingredients. Season well with salt and pepper. Set aside to cool.
For the chimichurri sauce: place all the ingredients in a glass jug and pulse until smooth with a stick blender. Should you not have a blender (or food processor) at your disposal, chop the parsley, garlic onion finer and mix with the rest of the ingredients. Season.
The pastry should be sufficiently chilled by now. Divide the pastry into three and place one third on a lightly floured surface and roll into a rectangle, to just under 1 cm thick. Cut the pastry into 6 x 6cm squares. Place 2 tbsp of the filling just of the center of the square and fold in half. Seal with your fingertips, then crimp the edges by folding it from one side to the other, to form a half moon shape. Repeat with the remainder of the pastry.
Heat the canola oil in a large pot over high heat. To check that it is ready, drop a small piece of pastry in the oil – if it sizzles, you are good to go.
Drop 4 to 5 of the empanadas in the hot oil (depending on the size of your pot – you do not want to overcrowd the pot) and agitate every now and to ensure you are browning both sides. Remove from the oil once golden brown and drain on kitchen towel. Sprinkle with a little salt.
Just before serving, combine all the ingredients for the coleslaw in a large bowl. Serve immediately with you fresh KOO Mixed Vegetable Empanadas and chimichurri.