It’s January, that austere window between the winter holidays and Valentine’s Day when we’ve overdosed on decadent food and haven’t yet crafted any excuses for cheating on our New Year’s resolutions. If your self-improvement list includes giving up meat, losing weight, or simply eating more healthfully, three excellent new vegetarian cookbooks can help. Useful for meat-loving “flexitarians” and ardent vegans alike, all three make veggies pleasurable rather than simply virtuous.

Not surprisingly given its title, “How to Cook Everything Vegetarian” (Wiley) by Mark Bittman is by far the most comprehensive of the trio. At almost 1,000 pages, it’s a virtual encyclopedia, with more than 2,000 recipes (plus variations) and extensive reference information on kitchen techniques — much of it illustrated with diagram-like black-and-white drawings.

“Everything” has something for everyone — or at least everyone but the dyed-in-the-wool carnivore. Sensitive to the needs of both the inexperienced and the busy, the book is easy to navigate, and the cooking times on the recipes I tried seemed fairly accurate. Yet it will not bore veteran cooks or those looking for impressive dinner party fare. While including all the basics, Mr. Bittman, the author of the bestselling book “How to Cook Everything” (Wiley), offers many imaginative and sophisticated dishes — so even jaded folks with shelves of vegetarian cookbooks will find new ideas here.

Particularly useful, the enlightening chapter on tofu details the wide range of soy products available and the myriad techniques for varying their flavors and textures. My only beef, so to speak, is that the otherwise thorough book never explains exactly how long to defrost tofu, saying only “allow enough time.” Because Mr. Bittman promised it would yield a “darker, firmer, chewier, and meatier brick,” I froze two small blocks and then assumed that six hours on my countertop would be more than ample defrosting time. It was not, and I eventually gave up and added still-icy tofu to the Braised Tofu and Peas in Curried Coconut Sauce, with passable but imperfect results.

If “How to Cook Everything Vegetarian” is a vegetarian’s encyclopedia, “Veganomicon” (Marlowe & Company) by Isa Chandra Moskowitz and Terry Hope Romero is a series of notes from your best friend and Mollie Katzen’s “The Vegetable Dishes I Can’t Live Without” (Hyperion) — a slim, but carefully selected collection of elegant recipes — is a volume of poetry. By far the most entertaining of the three, “Veganomicon” — like the Post Punk Kitchen Web site and TV programs the authors host — is informal and endearing, with a clever edge that will be particularly appealing to budget-conscious 20- and 30-somethings. In extolling the virtues of food processors, Ms. Moskowitz and Ms. Romero write, “If you can’t afford one right now, then get married simply so you can put this on your wedding registry.” Of glass and ceramic mixing bowls, they note,”your cat will knock them onto the floor and cause disaster, so only get them if you’re allergic to cats.”

Although its recipes are all devoid of animal products, “Veganomicon,” like the authors’ earlier books, avoids the self-righteous, judgmental rhetoric that plagues so many other vegan productions. For cooks who are not vegans — or even vegetarians — the recipes lend themselves to tasty adaptations. I, for one, decided to top the delicious Samosa Baked Potatoes with real yogurt and to serve the Sweet Potato-Pear Tzimmes with Pecans and Raisins as a sweet-savory side dish in a meat meal.

“Veganomicon” is user-friendly, packed with tips and instructions for a wide range of cooking techniques. Recipes are accompanied by a series of icons designating them everything from gluten-free to low fat to “under 45 minutes.” Don’t rely on the time estimates, however. Samosa Baked Potatoes claimed to take only 20 minutes after the initial potato baking session — impossible since, following various post-baking tasks, the dish then must cook for an additional 20 minutes.

You won’t have the same problem with Mollie Katzen’s “The Vegetable Dishes I Can’t Live Without,” however, because — annoyingly — none of the recipes include cooking times. “Vegetable Dishes,” which comes on the 30th anniversary of Ms. Katzen’s beloved classic “The Moosewood Cookbook,” disappoints in other ways as well. A slim volume, it features Ms. Katzen’s familiar hand lettering and decorative drawings but is sparser and less chatty than her earlier publications. Unlike “Everything,” and “Veganomicon,” both with a wide range of ingredients and dishes, including desserts, “Vegetable Dishes” is vegetables only and exclusively side dishes at that. While several recipes served together could easily make up a satisfying meal, the reader is left to his or her own devices when it comes to assembling such a repast, as few of the recipes offer serving suggestions.

Nonetheless, the dishes themselves are quite lovely. Arranged in alphabetical order by vegetable, from artichoke to zucchini, most of the recipes are light, flavorful, and simple to prepare. Ms. Katzen offers fresh inspirations for tried-and-true veggies — Coconut Ginger Carrots and Sesame-Walnut-Ginger Broccoli, for example — as well as a number of ideas for more unusual produce, such as fennel, parsnips, and escarole. The Greek-Style Spinach With Caramelized Onions, Tomatoes, Yogurt, and Pine Nuts was a palate-pleasing mélange of sweet, savory, tangy, and crunchy.

So before your New Year’s resolve wavers, pick up at least one of these books — and get thee to the produce aisle.

Greek-Style Spinach With Caramelized Onions, Tomatoes, Yogurt, and Pine Nuts

Adapted from “The Vegetable Dishes I Can’t Live Without” by Mollie Katzen

1 pound fresh spinach (do not use frozen spinach)
2 tablespoons olive oil
1 1/2 cups minced onion
1 teaspoon minced or crushed garlic
4 ounces chopped fresh tomatoes
Plain yogurt (regular or Greek style)
Toasted pine nuts
Freshly ground black pepper, to taste
Salt, to taste

1. Stem the spinach and wash the leaves.

2. Drain (you can leave a little water clinging to the leaves), and transfer to a cutting board. Coarsely chop and set aside.

3. Place a large, deep skillet or wok over medium heat. After about a minute, add the oil, and swirl to coat the pan. Add the onion, and cook for about five minutes, stirring often.* Sprinkle lightly with salt, reduce the heat to low, and continue to cook, stirring occasionally, for about 10 minutes longer, or until very soft and sweet.

4. Turn the heat back up to medium, and add the spinach and the garlic to the onion, sprinkling a little salt over the leaves. Use tongs to lift and stir the spinach as it cooks for about five minutes, or until just wilted and bright green.

5. Toss in the chopped tomatoes, and cook for just a few minutes longer, still turning with the tongs — until the tomato pieces are heated through.

6. Serve immediately, topping each serving with a dollop of yogurt, a light sprinkling of pine nuts, and a few grinds of black pepper.

Yield: 4 to 5 servings.

* You can cook the onions well ahead of time and leave them in the pan on the stove for up to several hours. Reheat the onions, and finish the dish shortly before serving.