Preheat your oven to 400°F.

Place the butternut squash cubes in a microwave-safe bowl and microwave on high for 2 minutes to partially soften them. They should be about halfway cooked, not fully tender.

In a large mixing bowl, combine the partially cooked squash, chopped bell pepper, zucchini slices, red onion chunks, and sliced kielbasa.

Drizzle the olive oil over the mixture, then sprinkle with dried thyme, smoked paprika, garlic salt, and black pepper.

Toss everything together until each piece is evenly coated with the oil and seasonings.

Lightly brush a rimmed baking sheet with olive oil (or line with parchment paper if you prefer, though it's not required).

Spread the vegetable and sausage mixture in a single layer on the prepared baking sheet.

Roast for 25 minutes, or until the vegetables are tender and the edges are lightly browned and caramelized.