In large skillet over medium-high heat, heat olive oil. Cook onions 1-2 minutes until translucent. Add mushrooms and ground beef. Cook about 5 minutes, or until beef is no longer pink. Stir in taco seasoning. Cook 2-3 minutes. Set aside.

Lay one large flour tortilla on flat surface. Spread 2 tablespoons mushroom-meat mixture on center of tortilla.

Drizzle dollop of nacho cheese over mushroom-meat mixture. Top meat with one tostada shell then spread thin layer of sour cream over tostada shell.

Top with shredded lettuce, diced tomatoes and shredded Mexican cheese then one small tortilla. Make sure not to overstuff so wrap doesn’t break apart while cooking.

Fold edges of large tortilla toward center until completely covered.

In hot skillet, generously spray with nonstick cooking spray. Carefully place wrap seam side down on skillet. Cook 2-3 minutes until golden brown.

Flip and cook other side until golden brown. Repeat with remaining mushroom-meat mixture, tortillas and toppings.

Cut wraps half and serve.