Put frying pan on a medium-high heat. Put some oil in. Once oil is hot, place the meat pieces in. Season with salt and pepper. Once they are fully cooked, set aside on a bowl.
Clean out your frying pan. Then add some more oil. Once oil is hot, place garlic slices in. Then put in carrots and onions slices. Stir them around.
Once garlic slices get a slight browning to them, place in the cabbage and bell pepper slices. Stir it around for another 30 seconds.
Add the udon noodles in. Then put in soy sauce, oyster sauce, sugar and water. Give it all a nice stir.
Add in the cooked beef slices. Then add in the mungbean sprouts and spring onion slices. Turn off the heat. (The mungbean sprouts will continue to cook from the residual heat).
Put a few shakes of black pepper in. Then plate-it-up. Garnish with spring onion slices. Place a fried egg over the top (optional). Enjoy!