Whisk together dressing ingredients and set aside. (You can take a taste but remember that it might seem a little strong - it'll become more tame once it's on the brussels sprouts and everything else).
Heat a large skillet over high heat. Add a few teaspoons of oil. When it starts to sizzle add the brussels sprouts, cut side down (or as many as you can get cut side down quickly), with a few pinches of salt. Don't touch them for a few minutes until the cut-side starts to turn golden brown (turn one over to check). Once they have a good sear, flip them over, add the broccolini and continue cooking until tender, but not mushy. At the very end, toss in the scallions.
Transfer the vegetables to a large plate, let them cool slightly, then toss with a bit of the dressing. Taste and adjust seasonings.
Toss the brussels sprouts & broccolini with the black rice, sliced avocado, mint, almonds, sprouts, and sesame seeds. Taste & toss with more dressing. Serve warm with extra lime slices and more sriracha if you like.
Notes
Vegan/vegetarians: sub soy sauce or tamari for the fish sauce, but add only 2 tablespoons, not ¼ cup. (you can always add more, to taste).
Feel free to roast your brussels sprouts & broccolini in the oven if you prefer.
Recipe by Love and Lemons at https://www.loveandlemons.com/brussels-sprout-avocado-salad/