Those who happen to have been laid off, downsized or just broke may have taken it upon themselves to make from scratch food they used to buy at the store. Or maybe some people just like to cook. Whatever, the DIY ethos is big in cooking right now.

Mill Valley’s Jennifer Reese found herself out of a job as Entertainment Weekly book critic. Walking through the grocery store, she always had the nagging feeling that she could and should be cooking from scratch instead of buying boxes and bottles of stuff. The loss of her job forced the issue, but it also raised a question in her mind: What if it actually cost more to make your own jelly, yogurt and ice cream?

The result of this line of thinking is Make the Bread, Buy the Butter (Free Press, $24), a funny but authoritative cookbook that breaks down what’s worth making from scratch and what’s not. Her analysis is based not just on dollars and cents but also on investments of time. Sure, you could make your own hot dogs, but the labor and cleanup required test one’s patience. I also like that Reese puts factors like sustainability and animal welfare in her calculations.

When she considers whether to make it or buy it, most of the time the answer is “make it.” That’s the subversive message that runs throughout the book. The food industry would like us to believe that fending for ourselves is far too difficult and that we need to buy mustard, bread, pesto, muffins and caramel corn in brightly colored packages. The reality is many of the foods we never considered making ourselves are ridiculously easy (check out Reese’s recipe for hot sauce: just chiles, vinegar, garlic and salt), and they usually taste infinitely better.

For example, a quart of sauerkraut costs $2 per quart to make at home while a quart of Bubbies-brand ‘kraut runs $5.70. If you’re fond of Reuben sandwiches, consider that making your own pastrami costs just $4 per pound while the store-bought stuff goes for as much as $15 a pound. It seems like a no-brainer, but Reese admits the hassle required to make your own pastrami is “prodigious.”

Her recipe for dill pickles is worth the purchase price alone. I love pickles, but I find myself hording them because they’re so pricey and they go so fast. But now I make my own, and they cost about $2 a quart, and they’re so much better than the ones from the store. Now I press pickles on anybody who come over. Want a pickle? Pickle? Pickles all around!

Devoted urban homesteaders might be committed to making everything themselves, but as a busy mom and blogger (www.tipsybaker.blogspot.com), Reese isn’t out to make herself a kitchen martyr. Consider her decision to punt when it comes to rice pudding. “Rice pudding is so dowdy and old-fashioned it seems like something you make at home. But I can’t make rice pudding better than Cozy Shack;the ingredient list is more than acceptable: milk, rice, sugar, eggs, salt, natural flavors. I give up. They win.”

But more often than not, you win in flavor and price by making it yourself. Reese shows you how.