Chicken Tostadas and Avocado Dressing

INGREDIENTS

• 2 tablespoons reduced-fat sour cream
• 2 tablespoons fat-free, lower-sodium chicken broth
• 2 tablespoons fresh lemon juice
• 2 teaspoons canola oil
• 1/4 teaspoon ground red pepper
• 1/8 teaspoon salt
• 1/2 ripe peeled avocado
• 1 1/2 tablespoons canola oil, divided
• 4 (6-inch) flour tortillas
• 2 garlic cloves, minced
• 1 jalapeño pepper, minced
• 2 cups shredded skinless, boneless rotisserie chicken breast
• 1 cup shredded iceberg lettuce
• 1/2 cup chopped tomato
• 1/4 cup (1 ounce) crumbled queso fresco