What I cook changes fairly often, but most of my weekday fixes are sub 30 minutes.
Of late, I've been on a bit of a pasta kick. It's simple, has plenty of variety and can be made pretty quickly.
(If you have kids, put your water on to boil and go Bath them while you wait)
Last night I made a carbonara , once the pasta was in I set about making the rest of the dish.
Took 2 rashers of bacon, sliced them into thin strips, and begin to fry. Added a clove of finely chopped garlic and a sprig of Rosemary also finely chopped. Once the bacon begins to Brown a little and the Rosemary and garlic start smelling good add an anchovy fillet (or w, or none, depending on taste) and also a good amount of fresh cracked pepper and a generous pinch of chilli flakes(optional).
Then chop 1 good sized tomato into about 1/2" dice. Add to the bacon mix and reduce heat. I also added about 1/3-1/2 cup of spinach. (I have a bag of frozen spinach portions, for quick meals like this I just thaw in the microwave till warm and squeeze out the excess water.)
By now, the pasta should be almost done. I then separate 2-3 eggs, putting the yokes in a small dish and wishing them. (my dogs get the whites as a bit of a treat, though you can save the whites for making meringue ). Now the pasta should be done, drain the pasta, but be sure to keep between 1/2 -1 cup of the pasta water.
Add the pasta to the bacon mix (turn the mix off if you haven't already) and gently toss through, then add about a 1/4 cup of the pasta water. Again, gently mix through, then add the lightly beaten egg yokes while stiring the mix. (Its important to keep stirring the egg thru otherwise it will cook before it can mix and will end up like scrambled egg).
From there, gradually add more pasta water till it's a nice silky creamy consistency. I also add a good handful of finely grated Pecorino or Parmesan, Wich I stir thru and add a little more water if required.
Serve immediately, with more grated cheese on top. Delicious.
I've made the same thing but using shallots and peas with the bacon. Or Basil and Cherry tomatoes with panchetta and toasted pine nuts.. and a few other variations. Once you've got the hang of using the egg yokes and pasta water it's pretty Universal. That said, if you're not using bacon or another fatty cured meat, add a tablespoon of butter to the veg that you're cooking.
Total Time from prep to plate is 15-20 minutes.