2 large fresh poblano chiles* (9 to 10 ounces total)
1 pound ground beef (15% fat)
1/2 cup coarsely grated zucchini
1/4 cup finely grated onion
1/4 cup panko (Japanese breadcrumbs)**
1 large egg, beaten to blend
2 garlic cloves, pressed
1 tablespoon ground cumin
1 teaspoon dried oregano (preferably Mexican), crumbled
1/2 teaspoon coarse kosher salt
1 tablespoon olive oil
1/2 small onion, coarsely grated
2 garlic cloves, minced
3 tablespoons pure ancho chile powder or pasilla chile powder*** (do not use blended chile powder)
2 teaspoons ground cumin
9 cups low-salt beef broth
1/2 teaspoon dried oregano (preferably Mexican)
1 cup coarsely grated zucchini
1/4 cup long-grain white rice
1/4 cup chopped fresh cilantro
1 tablespoon (or more) fresh lime juice
3 tablespoons (or more) vegetable oil
4 corn tortillas, cut into 1/4-inch-wide strips
Chopped fresh cilantro