I have a few.
Tomato sauce
3 tbsp oil
3 small red onions, peeled and chopped
2 Red Peppers, chopped
3 courgettes, chopped
3 carrots, peeled and chopped
3 stalks of celery, chopped
1 large pinch of dried oregano or mixed seasoning
6 400g tins of toms (but you could adjust that if you wanted)
2-3 garlic cloves (again adjust if your not a fan)
Heat enough oil to cover the bottom of a deep pan.
Fry onion, celery, pepper, courgette, carrot and garlic for 5-10 mins
Add the oregano and toms, then season.
Simmer for about 30mins.
Liquidise when cool and freeze the extra sauce.
I use that for loads of things. It's a good sub for bolognese orif I just fancy doing a simple dinner, just heat up and pour over fresh cooked pasta. You could do loads with it.
The other sauce which I find is a god send, is the Veloute sauces. It's a great staple because you can add different ingreadiants to suit what your eating.
To make 1/2 pint
3/4 pint/425ml veg stock (I very rarely have this in so use water and it's just as good)
1oz/25g butter
1oz/25g plain flour
2floz/ 60ml single cream (optional), I only use this when making the Garlic variety
salt an pepper to season
Melt the butter
Beat in the flour and cook on a low heat until it becomes a thick paste.
Remove from the heat and cool. Then add stock a little at a time until it keeps thickening up.
Bring back to the boil and keep stirring.
Turn down heat and simmer for 15 mins.
If using, add cream and bring back to simmer.
Variations - to be added at the simmering stage
Mushroom sauce - Add 2oz/60g chopped mushrooms
Tomato and basil - Add 3 tbsp of tom puree and basil
Garlic - Add 4 cloves of garlic and mixed herbs.
Again the tom and basil goes great with pasta or meats like chicken and pork.
The mushroom is another good pasta one, serve it up like a carbonara sauce with bacon etc.
The garlic one I use on loads of things. I think I've served it with all meats. It goes with everything.
The basic recipe to start you off is a great white sauce recipe so that does well for veg on sunday dinners and also gammon/bacon joints.
HTH