Start by cooking Udon noodles and corn separately and set aside.
Mince garlic, and in a small saucepan, mix together the sauce ingredients. Turn the heat up to medium or high until the sauce begins to boil, then turn the heat down to low until it is at a soft simmer. Let simmer for a few minutes, then turn off heat.
Spray a cast iron bowl or pan with cooking spray, then sauté minced garlic and onion until soft.
Next, add in the cooked udon noodles, add the corn on top, and add the small quarter tablespoon of butter on top. Also add the curry powder if you choose to do so.
Arrange the raw beef pieces around the noodles, and crack in the egg. Remove and pour the sauce and pepper on the beef and let the residual heat from the cast iron cook the meat. This is the way Pepper Lunch traditionally serves the dish, but you can also opt to finish cooking the meat on the stove if desired.
Top with scallions and bonito flakes and indulge in your delicious meal!