In a large pot, saute the onion and garlic gently in the olive oil until the onion is soft.
Add the carrots and cook gently for 5-10 minutes until the carrots begin to soften too.
Add the courgette and cook for a couple of minutes, then add the mushrooms and peas and cook for another couple of minutes.
Add the soya mince, vegetable stock, wine, tomato puree and brown sauce and stir in well. Bring to the boil, then reduce to a simmer, cover and cook for 30 - 40 minutes until the flavours have combined well and the sauce has thickened. Stir occasionally. When it is ready, season.
While the savoury mince is cooking, steam or boil your turnip, cauliflower and potato in separate pans. Once it is soft, mash and season the turnip, then mash together the cauliflower and potato with some butter and season this too.
Once everything is ready, assemble your two large pies. First fill each dish with savoury mince, then add a layer of turnip and finish with a layer of mashed cauliflower and potato.
Pop one dish in a pre-heated oven (200c/180c fan/gas mark
for about 20-25 minutes until the potato is golden and the dish is piping hot. Once cool, pop the other dish in the freezer to save for another night.