Photo: Courtesy of Beyond Sushi

For the eco-minded eater, sushi can feel like a guilty pleasure: Much of the fish is imported from overseas or farmed unsustainably, and a study by the International Union for Conservation of Nature found that more than 40 species of fish could vanish in the next few years, due largely to overfishing.

The next time you're seated at the sushi counter, you can check Monterey Bay Aquarium's handy mobile app for the best seafood choices (domestic Yellowfin tuna gets a green light, while Bluefin tuna is best avoided, both for the planet's sake and because of mercury concerns). Or you can skip the fish (and guilt) entirely and feast on vegetarian sushi. Guy Vaknin, the executive chef at Beyond Sushi, goes beyond the usual avocado-and-cucumber roll at his new restaurant, with creative combinations like asparagus and basil or kiwi and cucumber. We asked the former Hell's Kitchen contestant for tips on spotting worthy rolls at our local sushi joint or making your own at home (it's easier than you think!).

"Like any dish, you eat with your eyes first," Vaknin says. "Green on green can look boring, but picking a roll that has layers of color gets you more excited to eat." The rest, he says, is all about balance: Every soft texture, like avocado, should be paired with something crunchy, like carrots or daikon radishes. And sweet ingredients work well with a bit of spice (Beyond Sushi's mango and pickled jalapeno roll is too tasty to share—sorry, tablemates). And like most green tips, there's no need to think of it as an all-or-nothing proposition: Swapping one of your standard rolls for a vegetarian option each time you're out can add up to a big, happy impact on our oceans.