RETURNING to_jsonb(...)

How can the new record returned from RETURNING to converted to jsonb?

For example something like:

INSERT INTO my_table (a, b, c) VALUES ('a', 'b', 'c')
RETURNING to_jsonb(*);

or

UPDATE my_table SET a = 'a'
RETURNING to_jsonb(*);

or

INSERT INTO my_table (a, b, c) VALUES ('a', 'b', 'c')

ON CONFLICT DO UPDATE SET a = EXCLUDED.a

RETURNING to_jsonb(*);

Thanks in advance