Preheat and prep: Heat oven to 425°F (220°C).
Line a large sheet pan with parchment for easy cleanup.
Slice the kielbasa: Cut into 1/2-inch coins so they crisp without drying out.
Prep the veggies: Keep pieces similar in size for even cooking. Thinner carrots help them cook through.
Toss with oil and seasoning: Add vegetables and kielbasa to the pan. Drizzle with olive oil, sprinkle salt, pepper, smoked paprika, and red pepper flakes.
Toss to coat and spread in a single layer.
Start the roast: Bake for 12 minutes to begin caramelizing the edges.
Make the sauce: Stir together honey, garlic, soy sauce, Dijon, and vinegar. Taste and adjust—more honey for sweet, more soy for savory.
Sauce and finish: Pull the pan out, pour the sauce over, and toss well. Return to the oven for 8–12 minutes, until veggies are tender-crisp and kielbasa is browned and glossy.
Garnish and serve: Sprinkle parsley or sesame seeds.
Add a squeeze of lemon for brightness. Serve as is, or over brown rice, quinoa, or cauliflower rice.