Cook your base: Make your rice or grain according to package directions. Fluff and set aside.
For extra flavor, season cooked rice with a pinch of salt and a drizzle of sesame oil.
Mix the sauce: In a bowl, whisk soy sauce, water, honey, rice vinegar, sesame oil, ginger, garlic, and sriracha if using. In a separate small cup, stir together the cornstarch and water to form a slurry. Set both aside.
Prep the steak: Pat steak dry and slice thinly against the grain.
Season lightly with salt and pepper. If you have time, toss with 1 to 2 tablespoons of the teriyaki sauce to marinate while you prep the vegetables.
Stir-fry the vegetables: Heat 1 tablespoon oil in a large skillet or wok over medium-high heat. Add broccoli, bell peppers, snap peas, and carrots.
Stir-fry 4 to 6 minutes until crisp-tender. Season with a pinch of salt. Transfer to a plate.
Sear the steak: Add another 1/2 to 1 tablespoon oil to the pan if needed.
Increase heat to high. Add steak in a single layer without crowding (work in batches). Sear 1 to 2 minutes per side until browned and just cooked through.
Remove to a plate.
Thicken the sauce: Lower heat to medium. Pour the teriyaki sauce into the pan and bring to a simmer. Stir in the cornstarch slurry and cook 1 to 2 minutes until glossy and slightly thickened.
Combine: Return steak to the pan and toss to coat in the sauce.
If you like extra saucy bowls, add a splash of water and simmer briefly. Taste and adjust with more honey for sweetness or vinegar for brightness.
Assemble bowls: Divide rice among 4 to 5 meal prep containers. Top with steak and sauce, then add vegetables.
Finish with sesame seeds, green onions, and a squeeze of lime if you like.
Cool and store: Let bowls cool uncovered for 15 to 20 minutes, then seal and refrigerate.