To make the ceviche, place the mushrooms, two-third of the lime juice, the olive oil, and the salt in a mixing bowl; toss well and cover; marinate for 2hrs.
Place the onion, cucumber, tomatoes, avocado, garlic, chiles, orange juice, orange zest, oregano, cilantro, and remaining lime juice in a mixing bowl; add salt and pepper to taste; add the marinated mushrooms to the salsa mixture and combine.
To serve, divide the ceviche mixture among 8 martini glasses, and garnish with a wedge of lime and 4 toasted tortilla strips.
Source: The Artful Vegan