Heat oil in a large saucepan over medium heat. Add onion, carrot and celery and cook until softened, about 5 minutes.
Add garlic and thyme; cook for 1 minute more.
Add bay leaf, vegetable broth, tomatoes with their juice and chickpeas. Bring mixture to a boil; reduce heat to low and simmer for 15 minutes.
Stir in black beans and corn; simmer for 10 minutes more.
Meanwhile prepare dumplings according to package instructions. Drop spoonfuls of dumpling dough into the stew during the last 5 minutes of cooking time.