White Bean and Escarole Soup with Turkey Meatballs

1 lb. ground turkey 

1 egg 

1/4 cup grated Parmigiano-Reggiano cheese, plus shavings for garnish 

2 Tbs. dried bread crumbs 

1/4 tsp. salt 

1/8 tsp. freshly ground pepper 

2 cans (each 14 1/2 oz.) white beans 

1 head escarole 

2 Tbs. olive oil 

1 yellow onion, finely chopped 

2 garlic cloves, minced  

1/4 tsp. dried thyme  

1/2 cup dry white wine 

4 cups chicken broth