Preheat oven to 325 F. Place the roast in the bottom of a Dutch oven or roasting pan.
Whisk together the broth, tamari, miso, honey, vinegar, garlic, ginger, and red pepper flakes in a small bowl. Pour over your beef and toss to coat evenly.
Cover and roast for 3 hours. Remove from the oven and check for doneness. If the meat pulls apart easily already, shred it into large chunks and toss in the juices. If it does not pull apart easily, return it to the oven covered for 30 more minutes then shred and toss in the juices.
Once the meat has been shredded, increase oven temperature to 450 F and return to the oven uncovered to finish cooking for 15 minutes (I often like to push it to like 20-25), until the top layer of the meat is crispy.
While the meat is doing its last cooking, I whip up a simple coconut rice. Amounts are up to you, I use a 1:1:1 ratio, so 1/2 cup of jasmine rice, 1/2 cup of water, 1/2 cup of coconut milk (the kind from the can). Scale up or down as needed. Rinse the rice well, then add the water, coconut milk, and rice to a medium saucepan. Stir and cook on medium-high until it comes to a boil, then reduce to a simmer and cover.
Cook the rice for 15 minutes (covered at a simmer), stir halfway through, then remove from heat, put a folded-up tea towel on top of the pan and replace the lid. Let sit for 5 minutes, then fluff with a fork.
Serve the roast on the coconut rice and garnish with sesame seeds and green onion.