I hasten to add that this isn't actually boring, it acquired the tag in question when I was a student with limited cooking facilities and ended up eating the stuff several times a week. This made enough for two helpings, most of my day's food intake given that I was working from home. Just enough for it to be nice and not boring. Maybe the fact that I poured some leftover wine into it helped...
A pan of stock, either from a cube or from swilling out yeast extract jars. You know, the ones that don't have enough stuff in to scoop out and spread on toast but it seems wasteful to bin!
A tablespoon Bisto (powder not granules)
A tablespoon tomato puree
Three largeish carrots
Three sticks of celery
Half an onion
Half a normal tin of chopped tomatoes
Swill the yeast extract jars out with warm water. Stir slowly into the bisto. Add the tomato puree. Top up with more water and bring to the boil.
Chop the carrots, celery and onion and place in the boiling stock. Add the tomatoes. Turn the heat down and leave to simmer until the liquid has thickened and some has evaporated.
Eat with pasta. You don't need me to tell you how to cook that.