I have a few 15 minute meals. Some need thinking about the day before (have veg chopped etc, or set the oven to be hot when you walk in) whereas others are thrown together.
Pasta carbonara using fresh pasta:
Put a packet of lidl bacon lardons into a dry pan to fry
Turn on kettle
Slice an onion, add that to the pan once bacon is halfway cooked
In a jug, crack 2 eggs and add a good glug of double cream, decent grinding of pepper, mix well
Grate some parmesan cheese
Boil the pasta for 4 minutes (or use regular pasta for 12-15 and start it before the onion)
Strain pasta, keeping a cup of the boiling water
Toss in the bacon, onion and stir through
Add the liquid, stir well over a low heat, add some of the pasta water if needed to loosen it - you don't want eggs to curdle, just heat through and stiffen a little to a sauce
Serve
Can easily add mushrooms to the pan, or do it using chicken and mushrooms (can add a dash of white wine to the pan for flavor, if you use leftover cooked chicken it's a faster dish, tarragon is a nice herb to add to chicken versions). Chicken versions, or plain mushroom versions, both work well with rice instead of pasta.
A similar dish using prawns but not the creamy sauce, start with onion and garlic, add prawns (cooked or raw - only difference is a few extra minutes of cooking) and then some quartered tomatoes added to the pan to cook through.
Chicken fajitas are also fast -
Slice chicken into strips (can be done day before) and fry for 8-10 minutes. Add fajita seasoning and juice of a lime for 1 minute. Add 2 sliced peppers and a sliced onion, stir and cook for 3 more minutes. Meanwhile, heat wraps in microwave for 1 minute.
While the chicken has been cooking, you slice up the peppers, onion, then slice lettuce, tomatoes and grate cheese for table. Throw salsa and sour cream on table. Squish an avocado with a fork, add a pinch of chilli, some olive oil and lime juice, pinch salt - guacamole - or use a jar.
Serve.
Stir fries are also very fast - maybe 15-20 minutes. Using already cooked meat/fish can speed things up. And having veg chopped the night before means you can supervise arrival home chaos at the same time as cooking.
Or make your main sauce the day before to just heat up and cook fresh pasta/rice/potatoes. Like spag bol, curries, chilli, stews etc. Potatoes can cook in 10-15 minutes if you are going to make mash anyway - just chop them into smaller chunks to cook. You just get into the habit of immediately turning on the kettle when you walk in the door, and then using that to get something started. Empty bags and sort mail etc once you have things cooking.
Sauces like spag bol, chilli, loads of curries etc can all be made ahead of time and taste better - so I make those on a Sunday when I am already in the kitchen to use on a Monday often. And generally do at least 2 dinners worth in a batch, freezing one dinner portion for another night next week. That really helps.