Prepare rice noodles according to the instructions on the package, or as described in the recipe notes.
Drain the noodles and add 1 tbsp oil to prevent it from sticking. Set aside.
In a medium-sized bowl, mix together brown sugar, rice vinegar, soy sauce and fish sauce. This is the Pad Thai sauce.
Heat remaining 3 tbsp oil in a large non-stick skillet over medium-high heat. Add garlic and half of the green onion and sauté 1 minute. (Optional: Add red flakes)
Add carrots and sauté for 2 more minutes.
Push the mixture to the edge of the pan and add beaten eggs to the center. Cook and scramble until eggs have cooked through.
Add in bean sprouts and cook for 1 minute.
Add in shrimp and toss everything together and cook for about 3 minutes until shrimp turns pink.
Add noodles and sauce mixture to the skillet. Toss everything together and combine well.
Remove from heat. Squeeze fresh lime to taste along with peanuts, cilantro, more green onions. Serve and enjoy!