Crispy Ground Turkey Tostadas

Name: Crispy Ground Turkey Tostadas
Prep time: 30 min
Cook time: 29 min
Total time: 59 min
Cuisine: Mexican
Ingredients: 1 red onion, halved and thinly sliced; 0.25 cup Mexican crema; 2 limes; 0.25 teaspoon salt; 2 tablespoons vegetable oil, divided; 1 chayote - peeled, halved, seeded, and diced into 1/2-inch pieces; 1 poblano pepper - seeds and white ribs removed, diced into 1/2-inch pieces; 6 (6 inch) flour tortillas; cooking spray; 6 sprigs cilantro, minced, divided; 0.5 teaspoon onion powder; 1.25 pounds ground turkey; 0.25 cup water; 3 tablespoons taco seasoning mix; 1 teaspoon chili powder; 1 cup guacamole; 0.5 cup shredded Cheddar cheese