Host Christopher Kimball goes into the test kitchen with test cook Julia Collin Davison to learn how to make the ultimate black bean burgers at home. Next, tasting expert Jack Bishop challenges Chris to a tasting of vegetable broth. Then, test cook Becky Hays shows Chris how to make the freshest super greens soup with lemon-tarragon cream. Finally, test cook Dan Souza reveals the secrets to making homemade vegetable broth.