Preheat the oven to 425°F (220°C).
On a large rimmed baking sheet, combine the broccoli florets, minced garlic, sliced beef sausage, and 2 teaspoons of the chopped herbs.
Drizzle the olive oil over the mixture and season with kosher salt and black pepper.
Toss everything together until well coated, then spread the ingredients into an even layer on the sheet pan.
Roast in the oven for about 20 minutes, until the broccoli begins to brown.
Add the chopped bell peppers to the sheet pan and toss everything together.
Spread the mixture back into an even layer and return to the oven.
Roast for another 15–20 minutes until the sausage is browned and the vegetables are tender.
Remove from the oven and garnish with the remaining fresh herbs and grated Parmesan cheese if desired.
Serve the Sheet Pan Sausage and Vegetables warm.