Awesome

Vegetarian-Friendly Restaurants in San Francisco

Jay's Cheesesteaks (many seitan flavors)
Ike's Place (tons of amazing veggie sandwiches)
Toaster Oven (Potbelly's clone)
Freddie's Sandwiches (in north beach if you don't want to go all the way to, or wait in the line at, Ike's; get the jalapeno spread)
Rhea's Deli (Great seitan BBQ Chicken sandwhich, and cheese sandwhiches of the highest quality)
Love n Haight (lots of veggie meat options and open late)
Great American Grilled Cheese Kitchen (tons of great cheeses all melted together)

Papalote (their house salsa is the best IN THE WORLD)
El Buen Sabor (my favorite super veggie burrito)
Taqueria Cancún (classic mission burrito; open till 2am on fri/sat, 1am other days, I think)
Weird Fish (seitan tacos and sweet potato fries. yum!)
Gracias Madre (Vegan mexican food)
La Palma Mexicatessen (fresh hand-made tortillas)
El Tonayense (amazing southwestern grilled veggie burrito. There may be gristle, but it's amazing.)

Tsunami (awesomest veggie rolls and sake selection)
Chaya (all vegan japanese and sushi)
Minako (huge veggie & vegan menu, home-style japanese)
Ryoko (not all veggie, but the ones they have are the best)
Tatake (mostly not veggie, but the veggie options are amazing -- and sustainable)
Nihon (also many awesome veggie options -- sustainability unknown)

Yum Yum Hunan (get the Veggie Potstickers, General Tso Meatless Chicken, and Szechuan String Bean. Order outside of this selection at your own peril)
Golden Era (excellent selection of seitan fake meat dishes)
Big Lantern (Good selection of seiten fake meat)
Jasmine Tea House (veggie meats)
Shangri-La Chinese Vegetarian (all vegan. has medicinal dishes, too)

Pakwan (amazing Paneer Tika Masala, and many other veggie dishes)
Udupi Palace (all vegetarian south indian)
Kasa (indian food wraps. sounds weird; tastes good!; several locations)
Vik's Chaat (all veg south indian. amazing and authentic. check hours.)
Dosa (high-ish-end south indian. vegetarian-friendly. mission location more relaxed than fillmore.)

Sunflower (the best lunch special around. delicious soup and egg rolls)
Slanted Door ( The Lemongrass Tofu is so good that it was all I ordered there for years. )

Barney's Gourmet Hamburger (big selection of awesome veggie burgers. get the curly fries and a turkish coffee shake to round it out!)
Metro Cafe (Veggie Burgers & Cheese Steaks)

Suppenküche (not tons of veggie options, but they're all great, especially brunch)
Rosamunde Sausage Grill (tofurky sausage next to Toronado)

Marcellos (best thin crust)
Golden Boy (thick crust, good during a night of drinking up in North Beach)
Patxi's Pizza (best chicago style deep dish in the city)
Flour + Water
South Beach Cafe
Tony's Pizza Napoletana
Zero Zero (when it opens later this year. i'm assuming it'll be awesome because Picco's in Sausalito is awesome)
Pauline's

Tartine (super famous bakery. try the morning buns!)
Mama's (holy crap so amazing, get here if you can!)
Butler and the Chef (Veggie Eggs Benedict rules)
Dottie's (black bean cakes, zucchini cakes are good additions to the standard brunch fare)
Fatoush (the perfect brunch spot, especially on their back patio when it's nice out)
Pork Store Cafe (veggie brunch stuff including vegan option)
Mission Beach Cafe (daily brunch, great vegetarian options)
St Francis Fountain (diner-style breakfast / brunch, lots of veg options)
Boogaloo's (hipster delight, tofu scram)

Greens
Millennium (Vegan. Fantastic use of fungi)
Restaurant Gary Danko (if you ask for it beforehand, they have an amazing vegetarian prix fixe menu)
Cafe Gratitude (vegan raw food - [much] better than you'd expect)
Herbivore (a bit pricey, but delicious)
Loving Hut (vegan chain)
Outerlands (Menu changes every day, but they always have their incredible bread)

Easy Creole (pop up, Wednesday and Friday nights, awesome etouffee, easycreole.com)

Bi-rite Creamery (right next to the park and they offer 2 or 3 vegan options usually)
Humphrey Slocombe (bourbon and corn flake ice cream = secret breakfast!)
Maggie Mudd's (best vegan ice cream pretty much ever)
Mitchell's (ice cream the way you remember it from your childhood. tons of flavors)
Xanath Ice Cream (from the people who brought you the yellow gate that never opens, but smells of saffron and vanilla)

Ananda-Fuara, Market and 9th. Never been there, but it's a vegetarian restaurant.