You could make Jamie Oliver's very veggie sauce and then freeze it:
Very-veggie sauce Makes about 3 litres
3 tbsp olive oil
3 small onions, peeled and chopped
2 red peppers, chopped
3 courgettes, grated
3 carrots, grated
1 butternut squash, peeled and grated
1 large pinch dried oregano
2 bay leaves
6 400g tins plum tomatoes
This is a really useful base sauce, which is packed with vegetables. This recipe makes a 3-litre batch. Any surplus sauce can be frozen to use later to top pizzas or to add to stews. By adding a few leftover vegetables, it makes a great sauce for pasta.
Heat enough oil to cover the bottom of a large saucepan and fry the onion, pepper, courgette, carrot and butternut squash for 5 to 10 minutes. Add the oregano, bay leaves and tomatoes, then season with salt and pepper. Simmer for about 30 minutes. Allow to cool slightly before blitzing with a hand-blender until the sauce is smooth. Adjust seasoning to taste.