Whisk the soy sauce, honey, rice vinegar, cornstarch, and water together until smooth.
Heat half the oil in a large skillet or wok over medium-high heat. Stir-fry the onion, carrots, bell pepper, broccoli, and snow peas until crisp-tender and brightly colored, about 6 to 8 minutes.
Push the vegetables to the side. Add the remaining oil, garlic, and ginger, and cook for about 30 seconds until fragrant.
Pour in the sauce and toss everything together. Cook 2 to 3 minutes, stirring, until the sauce thickens and coats the vegetables.
Serve immediately over rice or noodles, spooning the glossy sauce over each portion.