Because the main ingredients to a stir fry are harvested at different times of the growing season. Items must be preserved to create not only stir fries, but egg rolls and spring rolls as well. Not to mention soups.
I also don't harvest with just the stir fries on my mind. I harvest and preserve with other specifics. The stir fries are, again, leftovers or a bit o'extras.
Pea pods. Use to jelly them, but I have more than enough jelly and jams to survive. Pea pods are now chopped and saved in the freezer for later use. I use a food saver with butcher quality bags. Each bag contains just enough of the pods for one meal.
Radishes, carrots, spinach, onion or scallions, pok choy, roasted turkey or chicken bits(from making deli sliced sandwich meats), cabbage, Red bell, red chile, and cilantro are all saved over the course of the spring and fall. sometimes depending on how feisty I am feeling other ingredients is stored as well. after you have squeezed the life out of a lemon, the left over slimy pulp and the zest freeze well.
We do two different sizes, family and individual. And yes, all out of extras. I rarely use an entire days harvest for one family recipe. And by the to me harvest is done and the garden is asleep, I have several wonderful meals waiting in the freezer.
I also no longer blanch anything. I know, some one will take issue with that. I did for years, but find it rather unnecessary for my needs. I can't stand blanched then frozen spinach. But that is a personal problem.
FYI, sesame oil does freeze, while soy sauce doesn't. If you are going to freeze some of your oils and sauces for your future stir fries, line an egg carton with foil, pour your required amount into it, then freeze over night to 48 hours. Place in your bag then add to your grouping.
Once the individual ingredients have been frozen, I separate them out into a gallon size food storage bag. At that point it is merely a grab and cook scenario.
As for the soups. As soon as something is harvested, I wash, and cube into small piece just enough of the veggie to cover one layer of my food dehydrator. Once dried I place it into a quart or pint jar, depending if it is for family or individual, and begin to layer the ingredients. Make sure the lid is on tight between layering. Once full, you can oven can it. When needed, merely pour into a pot of broth.
It's all rather simple, and treated as an afterthought, but boy oh boy is it a yummy after thought, as well as a slowly created premade meal for those winter days you are missing spring.