Heat sesame oil in a wok or large pan over medium heat.
Chop garlic clove and add to hot oil, stirring frequently until golden brown and fragrant
Add beef and cook until just a little color develops, about three minutes on each side.
While the beef cooks, chop the broccoli and bell pepper. If necessary, drain any excess liquid from the pan, then add the vegetables
Cook everything together on medium heat for about five minutes, stirring frequently.
In a small bowl, whisk together the Aminos, peanut butter, rice wine vinegar, and lime juice.
Add the mixture to the pan and continue to cook everything together for about five more minutes, stirring frequently to ensure the sauce is evenly distributed.
Evenly divide into meal prep containers. Top with cilantro and chili flakes, if desired.