I do all of the cooking, planning, and shopping. She occasionally does make up a marinade, sauce, or dressing though, and I'm a big fan of those, but I let her keep the recipes to use when she likes.
What do you have in your fridge/cupboard? That's the big question!
I imagine you keep cooking oil and vinegar. 1 cup oil, 1/3 cup vinegar, 1 tsp salt and whatever other seasonings you have on hand. Put them together in a cup, cover, and shake and you have a vinaigrette.
Using that I make hoisin sauce dressing. Oil, but not olive oil, rice vinegar or cider vinegar, 1 tbsp hoisin sauce, 1 tsp soy sauce instead of salt, garlic powder to taste. I use garlic powder because it will rehydrate and release its flavor in the vinegar, otherwise I generally use crushed garlic.
For a reduction sauce try this:
Diced shallots, or if no shallots 1/4 of a sweet onion and a clove of garlic will work.
1 tbsp butter
Sweat the shallots/onions & garlic in a small pan with the butter. Right when they turn translucent, add 1 cup red wine, one ice cube of frozen stock or 1 tbsp Better than Bouillon, 1 tsp salt and 1 tbsp brown sugar.
Whisk until salt and sugar dissolve, then boil until reduced to a syrup. It goes from liquid to syrup to a sticky spot in the bottom of an empty pan pretty quick, so watch it and stir frequently.
I try to keep stock on hand for this sort of thing, so I'll get bones from my butcher friend and make up a huge batch every so often, which I freeze in ice cube trays. If that isn't an option you can use beef broth or Better Than Buillon.
Pan gravy is one of my favorites because you can make it in the 10 minutes after cooking when you're resting the meat.
The ratio here is 2 fat to 3 flour, so have 2 tbsp fat and 3 tbsp flour waiting, scale up as needed.
When you've removed the meat from its pan, add the fat and flour and stir together until mixed, then splash 1/2 cup white wine or broth into the hot pan and quickly use a wooden spoon or spatula to scrape off all the good stuff stuck to the bottom. The French call this stuff "fond" which means base or bottom and wasting it is a sin.
Finally add 1/2 cup broth and continue to whisk over heat until it thickens. Taste and add seasonings as desired. It should be done by the time the meat is done resting.
Those are my go-to sauce recipes. Anything more complex isn't something I use on a regular basis, and these basic recipes can be modified as needed by changing out the various ingredients for others of the same type. You can use any oil or vinegar you like in the vinaigrette, any fat you want in the pan gravy, and any number of different wines and seasonings in the reduction.
The only recommendation I have is that when you make a wine reduction, you need to use a wine that you wouldn't mind drinking. In my opinion, cooking wine isn't meant for human consumption. I keep Red Diamond around as my red and a random dry reisling for my white.
And yes, I suck at making recipes. Sorry