Preheat your oven to 425°F and line a baking sheet with parchment paper.
Toss the baby carrots and halved potatoes with olive oil, salt, and pepper, then roast for 25–30 minutes until golden and tender, flipping halfway through.
While the veggies roast, heat olive oil in a large skillet over medium-high heat, season the beef with salt and pepper, and sear the strips in batches for 2–3 minutes per side until nicely browned.
In a small saucepan, whisk together soy sauce, water, brown sugar, honey, vinegar, garlic, and ginger, and bring to a simmer.
In a separate bowl, mix the cornstarch and water until smooth, then pour it into the sauce and simmer for another 1–2 minutes until thick and glossy.
Once all the beef is cooked, pour the sauce into the skillet, stir to coat the meat, and let it bubble for another minute so everything comes together.
To serve, spoon the roasted carrots and potatoes onto plates and top with saucy beef—add a sprinkle of sesame seeds or green onions if you want to dress it up.