2 tablespoons extra-virgin olive oil
1 onion, finely chopped
6 cloves garlic, thinly sliced
6 skinless, boneless chicken thighs, cut into 1/2-inch pieces
2 canned chipotle chiles in adobo sauce, finely chopped, plus 2 tablespoons adobo sauce
6 cups chicken broth
1/2 cup chopped fresh cilantro
Juice of 2 limes
Salt and pepper
1 hass avocado, thinly sliced lengthwise into 12 pieces
Crushed tortilla chips