Heat the vegetable oil in a large pan on a low heat
Add the onion, garlic, carrot, celery and courgette. Cook for 8-10 minutes until the onion has softened
Add the chopped tomatoes, vegetarian mince, tomato puree, balsamic vinegar, Marmite, vegetable stock cube, red wine stock cube, water and mixed herbs
Stir everything together and bring to a gentle simmer, simmer for 20 minutes
While it is simmering, prepare the potatoes and place into a pan of boiling water. Boil them for 15-20 minutes until soft, then drain them
Pre-heat your oven to 180C Fan/400F/Gas Mark 6Mash the potatoes up with the milk and butter
Add the lentils to the filling and stir them in. Then taste the filling mixture and add salt and pepper to your preference, then put it in your baking dish
Carefully top the filling with the mash potato. Run a fork all over the top to create texture (this helps to make the top lovely and crispy)Sprinkle the grated cheese all over the pie
Cook for 20-25 minutes until golden on top and bubbling
Remove from the oven and serve. Fully cooled leftovers can be stored in the fridge for 3 days or the freezer for 3 months
Notes
A white onion is perfect for this recipe, but if you have a red onion to use up instead then it won't make a huge difference.
I used Quorn mince for this recicpe, but you can use any vegetarian or vegan mince. If you don't want to use the mince, you can use mushrooms or crumbled tofu instead.
Marmite, also known as yeast extract, this is used for adding flavour to the sauce, but don't worry if you are a Marmite hater, your pie won't taste like Marmite!
You will need tinned green or brown lentils for this recipe, I have not tried this recipe with dried lentils.
I used regular white potatoes for topping this pie, but you can also top it with sweet potato, or even a mix of white and sweet potato.
I used a dried herb mix containing thyme, marjoram, parsley, oregano, sage, basil. If you don't have a mix then I suggest using thyme at a minimum, and rosemary too if you can. They add lovely fragrant flavour.
I always place a baking tray underneath my baking dish as pies like this can often bubble over the sides. Putting the dish on a baking tray, or placing a baking tray on the shelf underneath, saves you from having to clean spills from your oven.
For an extra crunchy topping you can sprinkle on some breadcrumbs as well as the cheese.
The ceramic dish I used to make this recipe was from Tesco and it measures 21cm in width, 31cm in length and 6cm in depth.
Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50).
For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.