Cook noodles according to package directions. (Note: Be very careful not to overcook the noodles. They will continue to cook slightly when added to the stir-fry.)
Stir together all ingredients for sauce. Taste the sauce and adjust, adding more honey if you'd like it more sweet, more soy sauce or fish sauce if you'd like it more salty. (Tasting and adjusting the sauce at this stage is important; some limes are more sour than others, so you may need to balance it out.) Set aside.
Set all of the ingredients near the stove. Put a Tablespoon measuring spoon in the sauce so you can add it to the noodles a little at a time.
Heat a large nonstick skillet, cast iron skillet, or wok over medium heat. Add 2 Tablespoons oil.
To heated oil, add tofu / chicken / shrimp and saute. When protein is browned on the outside (but not cooked all the way through), 2 Tablespoons sauce and bell pepper. Continue cooking until sauce coats protein and peppers are nearly tender, 2 to 3 minutes more.
Move protein and pepper to one side of the pan and add 1 Tablespoon of oil to the open space in the center. Pour eggs over oil. Scramble gently, 2 to 3 minutes.
Add noodles and 2 Tablespoons of sauce to the pan and stir until the noodles have absorbed the sauce. (The noodles should loosen up as they cook in the sauce, but add a splash of water if they stick together.)
Add all remaining sauce and continue cooking, gently folding everything together together until sauce cooks down and coats noodles, 2 to 3 minutes more.
Stir in green onions and about half of the peanuts (reserve the rest for sprinkling on top).
Divide between bowls and serve with toppings!