1/3 cup sour cream |
1/4 cup low-fat mayonnaise |
2 tablespoons whole-grain dijon mustard |
1 teaspoon dried tarragon |
1 teaspoon bottled minced garlic |
1/2 teaspoon salt, divided |
1/4 teaspoon black pepper, divided |
cooking spray |
1 (1-pound) boneless sirloin steak, trimmed |
1 (20-ounce) package refrigerated red potato wedges (such as simply potatoes) |