Easy Chicken-Mushroom Quesadillas

INGREDIENTS

• 2 cups cooked chopped skinless, boneless chicken breast (1 breast half)
• 1 teaspoon chili powder
• 4 (10-inch) whole-grain flour tortillas
• 3 cloves garlic, minced
• 1 tablespoon canola oil
• 8 ounces white button mushrooms, (about 3 cups)
• 1/4 teaspoon fresh ground black pepper
• 1 teaspoon ground cumin
• 1/2 cup salsa
• 1 cup shredded Mexican cheese mix or Cheddar
• 1/4 cup reduced-fat sour cream
• 2 cups baby spinach leaves, sliced into ribbons
• 1 teaspoon dried oregano
• 1/2 teaspoon salt
• 1 large onion, chopped (about 2 cups)