I think soup is the best thing about winter. It is amazing how leftovers can be transformed into warming bowls of yumminess with the addition of a bit of stock, softened onions/garlic and a quick blend together. Quite often H will have made a vegetable dish one day with a portion left over which, with a few simple additions, makes a quick and easy soup.
1. Start with your 'base'. For some people it's just garlic in oil, others use butter, I like chopped onions (half for one person, a whole for two people) and crushed garlic softened in olive oil.
2. Vegetables. The magic of vegetables, especially left over vegetables (E.g. mash potato or yesterday's side dish), is that most of them will work together in a soup! I recommend no more than three vegetables otherwise it just gets to busy. If in doubt, just Google the vegetables you have in the cupboard/fridge with the words 'soup recipe' and see what comes up! I normally end up combining a root veg (e.g. carrot, potato) with one or two vine vegetables (e.g. tomato, pepper, or courgette). Just add them to the base for a bit to either soften (if fresh) or to heat through (if a leftover). Now is the time to add any spices/flavourings, like salt, pepper or chili pepper but these are always optional and depends on the vegetables.
3. Boiling water: add the quantity you need for the thickness you want. I usually measure out the water with the bowl I'll use to serve it in, filling it to the amount I would serve (doing so once for one person, twice for two people etc.). You can always reduce it by simmering for longer, or add more later. I usually add one stock cube per person too to add a bit of extra flavour/saltiness, a vegetable stock is my go to.
4. Blend. Once the veg has been simmering for a while, 10-20 mins or so depending on the quantity and whether the ingredients are fresh or not, take it off the heat and blend away. I find the easiest thing to blend with is a good old hand held blender as it's quick and easy to clean. Of course you don't have to blend it, you can serve it as it is.
5. Cream (optional). If you did blend your soup and feel luxurious, stir in a bit of cream, or sour cream, and heat it back through slightly before serving. I find tomato soups, carrot soups, broccoli soups, pepper soups and of course mushroom soups taste good with a bit of cream!
Soups are usually really good the day after too as they have had time to thicken. You can change up a soup by adding a bit of spice, e.g. paprika, chili pepper or a mixed spice combination for bhryani, or by blending a soup that you ate 'chunky' originally.