Boil water in a large pot and cook flat rice noodles according to package instructions until al dente. Drain the noodles and set them aside for later use.
Heat vegetable oil in a large skillet or wok over medium-high heat until shimmering, ensuring it is hot enough for stir-frying.
Add minced garlic to the skillet and sauté for about one minute until fragrant, allowing its aroma to permeate the oil.
Introduce the protein of your choice (chicken or shrimp) into the skillet and stir-fry until cooked through—approximately three to five minutes for chicken or two to three minutes for shrimp.
Toss in sliced bell peppers, broccoli florets, and julienned carrots; stir-fry for another two minutes until they are slightly tender yet still crisp.
Add the cooked noodles back into the skillet along with soy sauce and brown sugar. Toss everything together thoroughly until well combined and heated through.
