Given the background description of some cooking related query, summarize the question into a title

Ex Input:
I am often making a basic leavened bread for some basic recipes, like naan, burek, focaccia, pizza, etc. However, I find that dry active yeast is prohibitively expensive, considering it is a self-replicating living organism. Is there a way to effectively create and store yeast for a reasonable period of time (~3 months) from a mother spore?

Ex Output:
How can I cultivate and store yeast?


Ex Input:
When we make polenta, we use polenta leftovers for lunch, grilling them.Are there any other uses for polenta leftovers?

Ex Output:
What can I use polenta leftovers for?


Ex Input:
When making e.g. spaghetti sauce, do I:first sweat the onions and then add the minced meat?first brown the minced meat and then add the onions?do both at the same time but in different pans and add them together afterwards?What are the advantages of preferring one of the options over the others?

Ex Output:

First onion or first minced meat?