BDD vs. TDD - No contest!

BDD (behavior driven development) is the practice of writing an executable testable specification that describes the application’s behavior. This specification is often written in a fluent interface, or in plain English
Testing features of the application and verifying the user requirements have been met.

While in TDD (Test Driven Development) the focus is on writing tests that single out units of the application. Using mocking or not there are basically three kinds of unit tests, happy, unhappy and edge case tests.

Integration tests are also of good,  making sure that the application runs end to end. e.g. the C# DAL(Data Access Layer) accessing the database and returning expected and unexpected results with the code dealing with both scenarios.

Red,Green, Re-factor, here you write the unit test prior to writing the code, it fails. Then you write the code to pass the test, the test passes. Does it need re-factoring? Now's the time  to do it. Does it meet the requirements? If not start over again and this time think more about what is required. It takes time, 6 months on average, to become a good TDD developer no matter what language you use.