In a medium saucepan, with heavy bottom, heat the oil over moderate heat. Add the ginger and garlic and cook for about 3 minutes, or until they begin to turn golden brown. Watch carefully so they don't overcook. Add sesame oil, chili oil and the black beans. Cook 1 minute, stirring constantly. Add the green onions and cook 2 minutes. Stir in the chili paste, tamari and stir to create a smooth sauce. Add the peanut butter and tahini, again stirring to create smoth paste. Cook 1 minute, stirring constantly. If you want a really thick sauce, add an additional TBSP of peanut butter and tahini.
Add the broth slowly and reduce the heat to low. Let the sauce simmer for a min of 15 minutes, as the flavors need to blend, and the broth thicken. Taste for spiciness - add more chili paste and chili oil if you want more heat. Saute ground beef, and when it is cooked through, spoon in some of the tan tan sauce and heat until liquid has been absorbed.
The sauce can be made 24 hours ahead of time; cover and refridgerate. Just before serving, bring back to temperature, but don't boil.
To serve: Place cooked noodles into individual serving bowls, top with beef, green onions, cilantro and peanuts. Ladle sauce over top.