In a small bowl, whisk together the tamari, gochujang, minced garlic, and grated ginger to create the savory stir-fry sauce.
Carefully remove the beef chuck meat from the rib bones and slice it into very thin strips against the grain for maximum tenderness.
Season the beef strips evenly with sea salt and black pepper.
In a separate bowl, toss the warm cooked rice with lime juice and lime zest until fragrant and well combined.
Heat avocado oil in a large skillet or wok over high heat until shimmering.
Add the beef in a single layer and sear for 2 minutes until a deep golden crust forms, then remove and set aside.
Add the broccoli and bell peppers to the same pan, stir-frying for 3-4 minutes until tender-crisp and slightly charred.
Return the beef to the pan, pour in the sauce, and toss everything together for 1 minute until the glaze is thick and glossy.
Divide the lime rice into bowls, top with the spicy beef stir-fry, and garnish with fresh avocado slices.